May 2025 - slurm-users - lists.schedmd.com

slurmctld keeps segfaulting, possibly during or just after backfill
by Marcus Lauer 21 Jun '26

21 Jun '26

We are running into a problem where slurmctld is segfaulting a few times a day. We had this problem with SLURM 23.11.8 and now with 23.11.10 as well, though the problem only appears on one of the several SLURM clusters we have, and all of them use one of those versions of SLURM. I was wondering if anyone has encountered a similar issue and has any thoughts on how to prevent this. Obviously we use "SchedulerType=sched/backfill" but strangely when I switched to sched/builtin for a while there were still slurmctld segfaults. We also set "SchedulerParameters=enable_user_top,bf_max_job_test=2000". I have tried turning those off but it did not help. I have also tried tweaking several other settings to no avail. Most of the cluster runs Rocky Linux 8.10 (including the slurmctld system) though we still have some Scientific Linux 7.9 compute nodes (we compile SLURM separately for those). Here is the crash-time error from journalctl: Oct 02 06:31:20 our.host.name kernel: sched_agent[2048355]: segfault at 8 ip 00007fec755d7ea8 sp 00007fec6bffe7e8 error 4 in libslurmfull.so[7fec7555a000+1f4000] Oct 02 06:31:20 our.host.name kernel: Code: 48 39 c1 7e 19 48 c1 f8 06 ba 01 00 00 00 48 d3 e2 48 f7 da 48 0b 54 c6 10 48 21 54 c7 10 c3 b8 00 00 00 00 eb da 48 8b 4f 08 <48> 39 4e 08 48 0f 4e 4e 08 49 89 c9 48 83 f9 3f 76 4e ba 40 00 00 Oct 02 06:31:20 our.host.name systemd[1]: Started Process Core Dump (PID 2169426/UID 0). Oct 02 06:31:20 our.host.name systemd-coredump[2169427]: Process 2048344 ( slurmctld) of user 991 dumped core. This is followed by a list of each of the dozen or so related threads. The one which is dumping core is first and looks like this: Stack trace of thread 2048355: #0 0x00007fec755d7ea8 bit_and_not (libslurmfull.so) #1 0x000000000044531f _job_alloc (slurmctld) #2 0x000000000044576b _job_alloc_whole_node_internal (slurmctld) #3 0x0000000000446e6d gres_ctld_job_alloc_whole_node (slurmctld) #4 0x00007fec722e29b8 job_res_add_job (select_cons_tres.so) #5 0x00007fec722f7c32 select_p_select_nodeinfo_set (select_cons_tres.so) #6 0x00007fec756e7dc7 select_g_select_nodeinfo_set (libslurmfull.so) #7 0x0000000000496eb3 select_nodes (slurmctld) #8 0x0000000000480826 _schedule (slurmctld) #9 0x00007fec753421ca start_thread (libpthread.so.0) #10 0x00007fec745f78d3 __clone (libc.so.6) I have run slurmctld with "debug5" level logging and it appears that the error occurs right after backfill considers a large number of jobs. Slurmctld could be failing at the end of backfill or when doing something which happens just after backfill runs. Usually this is the last message before the crash: [2024-09-25T18:39:42.076] slurmscriptd: debug: _slurmscriptd_mainloop: finished If anyone has any thoughts or advice on this that would be appreciated. Thank you. -- Marcus Lauer Systems Administrator CETS Group, Research Support

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Optimizing CPU allocation in Slurm with hyperthreading enabled
by Guillaume COCHARD 02 Mar '26

02 Mar '26

Hello, The Slurm documentation states that "The default allocation method within a node is cyclic allocation (allocate available CPUs in a round-robin fashion across the sockets within a node)." In our case, we are using hyperthreading, which means that if two jobs requesting one CPU each arrive at the same time on an empty node, they will be assigned to the two threads of the same physical core. To improve performance, we would like Slurm to allocate CPUs (in our case, threads) in a way that prioritizes using one thread per physical core first, and only once all cores are occupied, assign the second thread of each core. This would be similar to the Least Loaded Node (LLN) approach, but instead of distributing jobs across nodes, it would distribute them across physical cores (Least Loaded Core). We do not want to disable hyperthreading; we simply want to optimize core usage when a machine is not fully loaded. We also want this to be a cluster-wide setting, and not a user and/or job setting. Our current slurm.conf contains: ConstrainCores = no SelectType = select/cons_tres SelectTypeParameters = CR_CPU_MEMORY And our cgroup.conf contains: ConstrainDevices=yes ConstrainCores=yes Does anyone know how to achieve this? Thanks, Guillaume

3 2

slurmctld hourly: Unexpected missing socket error
by Jason Ellul 13 Jan '26

13 Jan '26

Hi all, I am hoping someone can help with our problem. Every hour after restarting slurmctld the controller becomes unresponsive to commands for 1 sec, reporting errors such as: [2024-07-15T11:45:48.509] error: slurm_send_node_msg: [socket:[934767]] slurm_bufs_sendto(msg_type=RESPONSE_JOB_INFO) failed: Unexpected missing socket error [2024-07-15T11:45:48.509] error: slurm_send_node_msg: [socket:[934760]] slurm_bufs_sendto(msg_type=RESPONSE_SLURM_RC) failed: Unexpected missing socket error [2024-07-15T11:45:48.509] error: slurm_send_node_msg: [socket:[934875]] slurm_bufs_sendto(msg_type=RESPONSE_JOB_INFO) failed: Unexpected missing socket error [2024-07-15T11:45:48.509] error: slurm_send_node_msg: [socket:[934906]] slurm_bufs_sendto(msg_type=RESPONSE_JOB_INFO) failed: Unexpected missing socket error [2024-07-15T11:45:48.509] error: slurm_send_node_msg: [socket:[939016]] slurm_bufs_sendto(msg_type=RESPONSE_JOB_INFO) failed: Unexpected missing socket error It occurs consistently at around the hour mark, but generally not at other times, unless we run a reconfigure or restart the controller. We don’t see any issues in the slurmdbd.log and the errors are also always msg type RESPONSE. We have tried building a new server on different infrastructure, but the problem has persisted. Yesterday we even tried updating slurm to v24.05.1 in the hope that may provide a fix. During our troubleshooting we have: Set: * SchedulerParameters = max_rpc_cnt=400,sched_min_interval=50000,sched_max_job_start=300,batch_sched_delay=20,bf_resolution=600,bf_min_prio_reserve=2000,bf_min_age_reserve=600 * SlurmctldPort = 6808-6817 But although the stats in sdiag have improved we still see the errors. On our monitoring software we also see a drop in network and disk activity during this 1 second, always at approx. 1 hour after restarting the controller. Many Thanks in advance Jason Jason Ellul Head - Research Computing Facility Office of Cancer Research Peter MacCallum Cancer Centre

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Assistance with Node Restrictions and Priority for Users in Floating Partition
by Manisha Yadav 28 Aug '25

28 Aug '25

Dear Team, I have a scenario where I need to provide priority access to multiple users from different projects for only 3 nodes. This means that, at any given time, only 3 nodes can be used in that partition, and if one user is utilizing all 3 nodes, no other user should be able to submit jobs to that partition, or their jobs should remain in the queue. To achieve this, I attempted to use QoS by creating a floating partition with some of the nodes and configuring a QoS with priority. I also set a limit with GrpTRES=gres/gpu=24, given that each node has 8 GPUs, and there are 3 nodes in total. I then attached the QoS to the partition and assigned it to the users who need access. I Also tried MaxTRES=gres/gpu=24 While this setup works as expected in the testing environment for CPUs, it is not functioning as intended in production, and it is not effectively restricting node usage in the partition. Could anyone provide suggestions or guidance on how to properly implement node restrictions along with priority? Thank you for your assistance. Best regards, Manisha Yadav ------------------------------------------------------------------------------------------------------------ [ C-DAC is on Social-Media too. Kindly follow us at: Facebook: https://www.facebook.com/CDACINDIA & Twitter: @cdacindia ] This e-mail is for the sole use of the intended recipient(s) and may contain confidential and privileged information. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies and the original message. Any unauthorized review, use, disclosure, dissemination, forwarding, printing or copying of this email is strictly prohibited and appropriate legal action will be taken. ------------------------------------------------------------------------------------------------------------

4 8

Wrong MaxRSS Behavior with cgroup v2 in Slurm
by Guillaume COCHARD 19 Jun '25

19 Jun '25

Hello, We've noticed a recent change in how MaxRSS is reported on our cluster. Specifically, the MaxRSS value for many jobs now often matches the allocated memory, which was not the case previously. It appears this change is due to how Slurm accounts for memory when copying large files, likely as a result of moving from cgroup v1 to cgroup v2. Here’s a simple example: copy_file.sh #!/bin/bash cp /distributed/filesystem/file5G /tmp cp /tmp/file5G ~ Two jobs with different memory allocations: Job 1 sbatch -c 1 --mem=1G copy_file.sh seff <jobid> Memory Utilized: 1021.87 MB Memory Efficiency: 99.79% of 1.00 GB Job 2 sbatch -c 1 --mem=10G copy_file.sh seff <jobid> Memory Utilized: 4.02 GB Memory Efficiency: 40.21% of 10.00 GB With cgroup v1, this script typically showed minimal memory usage. Now, under cgroup v2, memory usage appears inflated and depends on the allocated memory, which seems wrong. I believe this behavior aligns with similar issues raised by the Kubernetes community [1], and is consistent with how memory.current behaves in cgroup v2 [3]. According to Slurm’s documentation about cgroup v2, "this plugin provides cgroup's memory.current value from the memory interface, which is not equal to the RSS value provided by procfs. Nevertheless it is the same value that the kernel uses in its OOM killer logic." [2] While technically correct, this seems to mark a significant change in what MaxRSS and "Memory Efficiency" actually measure and renders those metrics almost useless. Our Configuration: ProctrackType=proctrack/cgroup TaskPlugin=task/cgroup,task/affinity Question: Is there a way to restore more realistic MaxRSS values — specifically, ones that exclude file-backed page cache — while still using cgroup v2? Thanks, Guillaume References: [1] https://github.com/kubernetes/kubernetes/issues/118916 [2] https://slurm.schedmd.com/cgroup_v2.html#limitations [3] https://facebookmicrosites.github.io/cgroup2/docs/memory-controller.html

3 4

Restrict and prioritize usage of certain nodes according to accounts
by thomas.hartmann＠th-ht.de 09 Jun '25

09 Jun '25

Hi, I'm going to have the following situation on my hands and I would like to ask for some suggestions how to solve this in slurm. We're talking about a cluster that is not yet operational so there are no real legacy configs that one needs to take into account. I have two sets of physical nodes: 1. node01 - nodeXX: General Purpose Nodes. Everybody can use them 2. project_A_01 - project_A_XX: These nodes come with some restrictions regarding who can and who must not run jobs on them. Users are organized into accounts, pseudohierarchically representing workgroups / projects etc within the university. For instance, there is going to be a "physics" account with "project_blackhole", "workgroup_miller" as children. Users are associated with one or more accounts. I have three sets of accounts (each can have child accounts): 1. "General" accounts: These are allowed to use all physical nodes. 2. "ForProfit" accounts: These absolutely must not use the project_A_* nodes 3. "Project_A" accounts: Their jobs should run first and foremost on the project_A_* nodes but they are also allowed to run on the node* nodes. My first idea would be to create two partitions, one with all nodes in there and a second one with only those nodes that the "ForProfit" are allowed to use. Using "AllowAccounts" or "DenyAccounts" would implement the restriction I need. In the future, there might be more project specific nodes for other projects. I would be grateful for any alternative solution or hints, how this could be solved optimally. Thanks a lot! Thomas

5 4

Slurm version 25.05 is now available
by Tim Wickberg 29 May '25

29 May '25

We are pleased to announce the availability of Slurm 25.05. The release notes summarizing the new features, and including links to the corresponding documentation, can be found at: https://slurm.schedmd.com/release_notes.html A more extensive list of changes are available in the CHANGELOG: https://github.com/SchedMD/slurm/blob/slurm-25.05/CHANGELOG/slurm-25.05.md The Slurm documentation has also been updated to the 25.05 release: https://slurm.schedmd.com Slurm can be downloaded from: https://www.schedmd.com/download-slurm/ -- Tim Wickberg Chief Technology Officer, SchedMD LLC Commercial Slurm Development and Support

1 0

Slurm accounts managed via ansible
by Ratnasamy, Fritz 28 May '25

28 May '25

Hi, I was wondering whether there might be built in support for managing slurm accounts,users,associations in ansible. it would be nice to be able to organize accounts in a yaml style file and modify accounts settings via gitlab CI/CD. For example, in a format as such: accounts: - name: "Boss1" parent: "root" description: "Big Boos" fairshare: 20 - name: "UnderBoss1" parent: "root" description: "working for Boss1" fairshare: 1 users: -username: "user1" -username: "user2" *Fritz Ratnasamy* Data Scientist Information Technology

3 2

Account getting duplicated
by Ratnasamy, Fritz 27 May '25

27 May '25

Hi, the slurm db duplicates all our account associations. one with cluster=cluster and another where cluster=venus (which is our actual cluster). is that intended? Or should I make any changes? *Fritz Ratnasamy*Data Scientist Information Technology

2 1

Slurm Reporting Difference between sreport and sacct
by Passant Hafez 23 May '25

23 May '25

Hi all, I was wondering if someone can help explaining this discrepancy. I have different values for project gpu consumption using sreport vs sacct (+ some calculations) This is an example that shows this: sreport -t hours -T gres/gpu cluster AccountUtilizationByuser start=2025-04-01 end=2025-04-05 | grep project1234 gives 178 while sacct -n -X --allusers --accounts=project1234 --start=2025-04-01 --end=2025-04-05 -o elapsedraw,AllocTRES%80,user,partition gives 213480 billing=128,cpu=128,gres/gpu=8,mem=1000G,node=2 gpuplus 249507 billing=128,cpu=128,gres/gpu=8,mem=1000G,node=2 gpuplus 13908 billing=64,cpu=64,gres/gpu=4,mem=500G,node=1 gpuplus 9552 billing=64,cpu=64,gres/gpu=4,mem=500G,node=1 gpuplus 4 billing=16,cpu=16,gres/gpu=1,mem=200G,node=1 gpu 11 billing=16,cpu=16,gres/gpu=1,mem=200G,node=1 gpu ... I will not bore you with the full output and its calculation, but the first job alone consumed 213480 seconds/60/60 * 8 gpus that's 474.4 gpu hours which is way more than the 178 hrs reported by sreport Any clue why these are inconsistent? or how sreport calculated the 178 value? All the best, Passant

3 3

Crash in "slurmd -C" when latest NVIDIA drivers are used
by Taras Shapovalov 22 May '25

22 May '25

Hello, Does someone have idea why "slurmd -C" crashes when it unloads gpu_nrt.so with latest NVIDIA drivers (570 and 575)? We checked, there is no crash in cuda at the moment and gpu_nvml.so works fine, all nvml calls finish successfully, dlclose on gpu_nvml.so works fine. The crash does not depend whether real GPUs present or not. Steps to reproduce: 1. Install Ubuntu 24.04 2. wget https://download.schedmd.com/slurm/slurm-24.11.4.tar.bz2<https://download.schedmd.com/slurm/slurm-24.11.4.tar.bz2;> 3. tar fx ./slurm-24.11.4.tar.bz2 4. cd slurm-24.11.4 5. apt-get install cuda-12-8 hwloc libmunge-dev -y 6. ./configure 7. make && make install 8. Run "slurmd -C", or sometimes "slurmd -vvv -C" to get the crash. Stack trace: #0 0x0000155555544b2a strlen (ld-linux-x86-64.so.2 + 0x28b2a) #1 0x000015555551fc08 __GI__dl_exception_create (ld-linux-x86-64.so.2 + 0x3c08) #2 0x000015555551d298 __GI__dl_signal_error (ld-linux-x86-64.so.2 + 0x1298) #3 0x000015555551e81d _dl_close (ld-linux-x86-64.so.2 + 0x281d) #4 0x000015555551d51c __GI__dl_catch_exception (ld-linux-x86-64.so.2 + 0x151c) #5 0x000015555551d669 _dl_catch_error (ld-linux-x86-64.so.2 + 0x1669) #6 0x0000155554e97c73 _dlerror_run (libc.so.6 + 0x97c73) #7 0x0000155554e979a6 __dlclose (libc.so.6 + 0x979a6) #8 0x0000155555388a25 gpu_plugin_fini (libslurmfull.so + 0x188a25) #9 0x000015555538f2ef gres_get_autodetected_gpus (libslurmfull.so + 0x18f2ef) #10 0x0000555555564828 _print_config (slurmd + 0x10828) #11 0x0000155554e2a1ca __libc_start_call_main (libc.so.6 + 0x2a1ca) #12 0x0000155554e2a28b __libc_start_main_impl (libc.so.6 + 0x2a28b) #13 0x000055555555fc75 _start (slurmd + 0xbc75) I don't really think the problem is in gpu_nrt itself, seems the problem is in memory corruption somewhere else, but I am not sure. The issue is reproduced constantly. A Best regards, Taras

2 3

Slurm 24.11.x + pyxis + TaskProlog -> fail
by Stefan Staeglich 21 May '25

21 May '25

Hi, we are currently evaluating Slurm 24.11. We are using pyxis in our cluster and have encountered the following problem in connection with TaskProlog: https://github.com/NVIDIA/pyxis/issues/163 Do you know more about the problem and the cause? Best, Stefan

1 0

sacctmgr: error: Sending PersistInit msg: Connection refused
by Ratnasamy, Fritz 18 May '25

18 May '25

Hi, We are working on a test cluster with slurm 24.11.3 and I am getting this error message from the login or compute nodes (note that the error does not show when run from the controller node): sacctmgr list associations tree format=cluster,account,user,maxnodes sacctmgr: error: _open_persist_conn: failed to open persistent connection to host:localhost:6819: Connection refused sacctmgr: error: Sending PersistInit msg: Connection refused Does someone know how fix that issue? Thanks, *Fritz Ratnasamy*Data Scientist Information Technology

2 1

New version of slurm
by Ratnasamy, Fritz 16 May '25

16 May '25

Hi, I am trying to install the new version of slurm. Do you know if there is a way to find out what support is compiled into the executables? For example, apache has httpd -L which shows all the loaded modules. See below result: [image: image.png] *Fritz Ratnasamy*Data Scientist Information Technology

3 2

slurmdbd - error: We can't find assoc 1 on cluster slurm
by Edmundo Carmona Antoranz 14 May '25

14 May '25

Hello! We are hitting this problem when we are making a first run of slurmdbd: [2025-05-13T13:29:08.916] debug4: accounting_storage/as_mysql: _get_parent_id: 10(as_mysql_assoc.c:699) query select id_assoc, lineage from "slurm_assoc_table" where user='' and deleted!=1 and acct='root'; [2025-05-13T13:29:08.916] debug5: assoc_mgr_fill_in_assoc: looking for assoc of user=(null)(4294967294), acct=(null), cluster=slurm, partition=(null) [2025-05-13T13:29:08.916] debug2: _find_assoc_rec_id: no associations added yet [2025-05-13T13:29:08.916] error: We can't find assoc 1 on cluster slurm I checked and up to that moment the table slurm_assoc_table has not getting a record inserted after the table has been created. [root@ea-r9-29504-pid1 ~]# grep -C1 slurm_assoc_table /var/log/slurmdbd [2025-05-13T13:29:06.666] debug2: DBD_ADD_CLUSTERS: called in CONN 10 [2025-05-13T13:29:06.719] debug4: Table "slurm_assoc_table" doesn't exist, adding [2025-05-13T13:29:06.720] debug2: query alter table "slurm_assoc_table" modify `creation_time` bigint unsigned not null, modify `mod_time` bigint unsigned default 0 not null, modify `deleted` tinyint default 0 not null, modify `comment` text, modify `flags` int unsigned default 0 not null, modify `is_def` tinyint default 0 not null, modify `id_assoc` int unsigned not null auto_increment, modify `user` tinytext not null default '', modify `acct` tinytext not null, modify `partition` tinytext not null default '', modify `parent_acct` tinytext not null default '', modify `id_parent` int unsigned not null, modify `lineage` text, modify `lft` int not null default 0, modify `rgt` int not null default 0, modify `shares` int default 1 not null, modify `max_jobs` int default NULL, modify `max_jobs_accrue` int default NULL, modify `min_prio_thresh` int default NULL, modify `max_submit_jobs` int default NULL, modify `max_tres_pj` text not null default '', modify `max_tres_pn` text not null default '', modify `max_tres_mins_pj` text not null default '', modify `max_tres_run_mins` text not null default '', modify `max_wall_pj` int default NULL, modify `grp_jobs` int default NULL, modify `grp_jobs_accrue` int default NULL, modify `grp_submit_jobs` int default NULL, modify `grp_tres` text not null default '', modify `grp_tres_mins` text not null default '', modify `grp_tres_run_mins` text not null default '', modify `grp_wall` int default NULL, modify `priority` int unsigned default NULL, modify `def_qos_id` int default NULL, modify `qos` blob not null default '', modify `delta_qos` blob not null default '', drop primary key, add primary key (id_assoc), drop index udex, add unique index udex (user(42), acct(42), `partition`(42)), drop key lft, add key lft (lft), drop key account, add key account (acct(42)); [2025-05-13T13:29:06.729] debug3: query insert into table_defs_table (creation_time, mod_time, table_name, definition) values (1747135746, 1747135746, '"slurm_assoc_table"', 'alter table \"slurm_assoc_table\" modify `creation_time` bigint unsigned not null, modify `mod_time` bigint unsigned default 0 not null, modify `deleted` tinyint default 0 not null, modify `comment` text, modify `flags` int unsigned default 0 not null, modify `is_def` tinyint default 0 not null, modify `id_assoc` int unsigned not null auto_increment, modify `user` tinytext not null default \'\', modify `acct` tinytext not null, modify `partition` tinytext not null default \'\', modify `parent_acct` tinytext not null default \'\', modify `id_parent` int unsigned not null, modify `lineage` text, modify `lft` int not null default 0, modify `rgt` int not null default 0, modify `shares` int default 1 not null, modify `max_jobs` int default NULL, modify `max_jobs_accrue` int default NULL, modify `min_prio_thresh` int default NULL, modify `max_submit_jobs` int default NULL, modify `max_tres_pj` text not null default \'\', modify `max_tres_pn` text not null default \'\', modify `max_tres_mins_pj` text not null default \'\', modify `max_tres_run_mins` text not null default \'\', modify `max_wall_pj` int default NULL, modify `grp_jobs` int default NULL, modify `grp_jobs_accrue` int default NULL, modify `grp_submit_jobs` int default NULL, modify `grp_tres` text not null default \'\', modify `grp_tres_mins` text not null default \'\', modify `grp_tres_run_mins` text not null default \'\', modify `grp_wall` int default NULL, modify `priority` int unsigned default NULL, modify `def_qos_id` int default NULL, modify `qos` blob not null default \'\', modify `delta_qos` blob not null default \'\', drop primary key, add primary key (id_assoc), drop index udex, add unique index udex (user(42), acct(42), `partition`(42)), drop key lft, add key lft (lft), drop key account, add key account (acct(42));') on duplicate key update definition='alter table \"slurm_assoc_table\" modify `creation_time` bigint unsigned not null, modify `mod_time` bigint unsigned default 0 not null, modify `deleted` tinyint default 0 not null, modify `comment` text, modify `flags` int unsigned default 0 not null, modify `is_def` tinyint default 0 not null, modify `id_assoc` int unsigned not null auto_increment, modify `user` tinytext not null default \'\', modify `acct` tinytext not null, modify `partition` tinytext not null default \'\', modify `parent_acct` tinytext not null default \'\', modify `id_parent` int unsigned not null, modify `lineage` text, modify `lft` int not null default 0, modify `rgt` int not null default 0, modify `shares` int default 1 not null, modify `max_jobs` int default NULL, modify `max_jobs_accrue` int default NULL, modify `min_prio_thresh` int default NULL, modify `max_submit_jobs` int default NULL, modify `max_tres_pj` text not null default \'\', modify `max_tres_pn` text not null default \'\', modify `max_tres_mins_pj` text not null default \'\', modify `max_tres_run_mins` text not null default \'\', modify `max_wall_pj` int default NULL, modify `grp_jobs` int default NULL, modify `grp_jobs_accrue` int default NULL, modify `grp_submit_jobs` int default NULL, modify `grp_tres` text not null default \'\', modify `grp_tres_mins` text not null default \'\', modify `grp_tres_run_mins` text not null default \'\', modify `grp_wall` int default NULL, modify `priority` int unsigned default NULL, modify `def_qos_id` int default NULL, modify `qos` blob not null default \'\', modify `delta_qos` blob not null default \'\', drop primary key, add primary key (id_assoc), drop index udex, add unique index udex (user(42), acct(42), `partition`(42)), drop key lft, add key lft (lft), drop key account, add key account (acct(42));', mod_time=1747135746; [2025-05-13T13:29:06.775] debug4: Table "slurm_assoc_usage_day_table" doesn't exist, adding -- [2025-05-13T13:29:08.916] debug4: accounting_storage/as_mysql: _get_parent_id: 10(as_mysql_assoc.c:699) query select id_assoc, lineage from "slurm_assoc_table" where user='' and deleted!=1 and acct='root'; [2025-05-13T13:29:08.916] debug5: assoc_mgr_fill_in_assoc: looking for assoc of user=(null)(4294967294), acct=(null), cluster=slurm, partition=(null) -- [2025-05-13T13:29:08.921] debug4: accounting_storage/as_mysql: _set_assoc_lft_rgt: 10(as_mysql_assoc.c:737) query select lft, rgt from "slurm_assoc_table" where id_assoc=2; [2025-05-13T13:29:08.922] debug4: accounting_storage/as_mysql: _make_sure_user_has_default_internal: 10(as_mysql_assoc.c:401) query select distinct is_def, acct from "slurm_assoc_table" where user='root' and deleted!=1 ORDER BY is_def desc, creation_time desc LIMIT 1; [2025-05-13T13:29:08.924] debug4: accounting_storage/as_mysql: as_mysql_add_assocs: 10(as_mysql_assoc.c:3999) query Even though the message shows up in the logs as an _error_, the service is able to come up fine, by the way, but is there an easy way to avoid the error message in the first place? BR!

1 0

Slurm release candidate version 25.05.0rc1 is available for testing
by Marshall Garey 13 May '25

13 May '25

We are pleased to announce the availability of Slurm release candidate 25.05.0rc1. To highlight some new features coming in 25.05: - Support for defining multiple topology configurations, and varying them by partition. - Support for tracking and allocating hierarchical resources. - Dynamic nodes can be dynamically added to the topology. - topology/block - Allow for gaps in the block layout. - Support for encrypting all network communication with TLS. - jobcomp/kafka - Optionally send job info at job start as well as job end. - Support an OR operator in --license requests. - switch/hpe_slingshot - Support for > 252 ranks per node. - switch/hpe_slingshot - Support mTLS authentication to the fabric manager. - sacctmgr - Add support for dumping and loading QOSes. - srun - Add new --wait-for-children option to keep the step running until all launched processes have been launched (cgroup/v2 only). - slurmrestd - Add new endpoint for creating reservations. This is the first release candidate of the upcoming 25.05 release series, and represents the end of development for this release, and a finalization of the RPC and state file formats. If any issues are identified with this release candidate, please report them through https://bugs.schedmd.com against the 25.05.x version and we will address them before the first production 25.05.0 release is made. Please note that the release candidates are not intended for production use. A preview of the updated documentation can be found at https://slurm.schedmd.com/archive/slurm-master/ . Slurm can be downloaded from https://www.schedmd.com/download-slurm/. The changelog for 25.05.0rc1 can be found here: https://github.com/SchedMD/slurm/blob/master/CHANGELOG/slurm-25.05.md#chang… -- Marshall Garey Release Management, Support, and Development SchedMD LLC - Commercial Slurm Development and Support

1 0

Performance Issues after Update to 24.11.5
by Tilman Hoffbauer 13 May '25

13 May '25

Hello, we are running a SLURM-managed cluster with one control node (g-vm03) and 26 worker nodes (ouga[03-28]) on Rocky 8. We recently updated from 20.11.9 through 23.02.8 to 24.11.0 and then 24.11.5. Since then, we are experiencing performance issues - squeue and scontrol ping are slow to react and sometimes deliver "timeout on send/recv" messages, even with only very few parallel requests. We did not experience these issues with SLURM 20.11.9 before, we did not check the intermediate version 23.02.8 in detail before. In the log of slurmctld, we can also find messages like slurmctld: error: slurm_send_node_msg: [socket:[1272743]] slurm_bufs_sendto(msg_type=RESPONSE_JOB_INFO) failed: Unexpected missing socket error We thus implemented all recommendations from the high throughput documentation, and did achieve improvements with it (most notably by increasing the maximum number of open files and increasing MessageTimeout and TCPTimeout). For debugging, I attached the slurm.conf, the sdiag output (the server thread count is almost always 1 and sometimes increases to 2), the slurmctld log and the slurmdbd log from a time of high load. We would be very thankful for any input on how restore the old performance. Kind Regards, Tilman Hoffbauer

2 4

Do I have to hold back RAM for worker nodes?
by Xaver Stiensmeier 13 May '25

13 May '25

Dear Slurm-User List, currently, in our slurm.conf, we are setting: SelectType: select/cons_tres SelectTypeParameters: CR_Core and in our node configuration /RealMemory /was basically reduced by an amount to make sure the node always had enough RAM to run the OS. However, this is apparently now how it is supposed to be done: Lowering RealMemory with the goal of setting aside some amount for the OS and not available for job allocations will not work as intended if Memory is not set as a consumable resource in *SelectTypeParameters*. So one of the *_Memory options need to be enabled for that goal to be accomplished. (https://slurm.schedmd.com/slurm.conf.html#OPT_RealMemory) This leads to four questions regarding holding back RAM for worker nodes. Answers/help with any of those questions would be appreciated. *1.* Is reserving enough RAM for the worker node's OS and slurmd actually a thing you have to manage? *2.* If so how can we reserve enough RAM for the worker node's OS and slurmd when using CR_Core? *3.* Is that maybe a strong argument against using CR_Core that we overlooked? And semi-related: https://slurm.schedmd.com/slurm.conf.html#OPT_RealMemory talks about taking a value in megabytes. *4.* Is RealMemory really expecting megabytes or is it mebibytes? Best regards, Xaver

6 8

slurm failing to start as it doesnt know its node name??????
by Steven Jones 12 May '25

12 May '25

Hi, I am not sure what i have missed but I am getting this error on a compute node. ====== root@vm01no16 ~]# systemctl status slurmd.service × slurmd.service - Slurm node daemon Loaded: loaded (/usr/lib/systemd/system/slurmd.service; enabled; preset: disabled) Active: failed (Result: exit-code) since Sun 2025-05-11 23:01:29 UTC; 15min ago Process: 1178 ExecStart=/usr/sbin/slurmd --systemd $SLURMD_OPTIONS (code=exited, status=1/FAILURE) Main PID: 1178 (code=exited, status=1/FAILURE) CPU: 3ms May 11 23:01:29 vm01no16.ods.vuw.ac.nz systemd[1]: Starting Slurm node daemon... May 11 23:01:29 vm01no16.ods.vuw.ac.nz slurmd[1178]: slurmd: fatal: Unable to determine this slurmd's NodeName May 11 23:01:29 vm01no16.ods.vuw.ac.nz slurmd[1178]: fatal: Unable to determine this slurmd's NodeName May 11 23:01:29 vm01no16.ods.vuw.ac.nz systemd[1]: slurmd.service: Main process exited, code=exited, status=1/FAIL> May 11 23:01:29 vm01no16.ods.vuw.ac.nz systemd[1]: slurmd.service: Failed with result 'exit-code'. May 11 23:01:29 vm01no16.ods.vuw.ac.nz systemd[1]: Failed to start Slurm node daemon. [root@vm01no16 ~]# uname -a Linux vm01no16.ods.vuw.ac.nz 5.14.0-503.40.1.el9_5.x86_64 #1 SMP PREEMPT_DYNAMIC Wed Apr 30 17:38:54 UTC 2025 x86_64 x86_64 x86_64 GNU/Linux [root@vm01no16 ~]# vi /etc/hosts [root@vm01no16 ~]# cat /etc/hostname vm01no16.ods.vuw.ac.nz [root@vm01no16 ~]# tail /etc/hosts # Entry for int01no9.ods.vuw.ac.nz 130.195.87.29 int01no9.ods.vuw.ac.nz int01no9.ods.vuw.ac.nz-default # Entry for vm01no13.ods.vuw.ac.nz 130.195.87.41 vm01no13.ods.vuw.ac.nz vm01no13.ods.vuw.ac.nz-default # Entry for vm01no14.ods.vuw.ac.nz 130.195.87.42 vm01no14.ods.vuw.ac.nz vm01no14.ods.vuw.ac.nz-default # Entry for vm01no15.ods.vuw.ac.nz 130.195.87.43 vm01no15.ods.vuw.ac.nz vm01no15.ods.vuw.ac.nz-default # Entry for vm01no16.ods.vuw.ac.nz 130.195.87.44 vm01no16.ods.vuw.ac.nz vm01no16.ods.vuw.ac.nz-default [root@vm01no16 ~]# ====== regards Steven Jones B.Eng (Hons) Technical Specialist - Linux RHCE Victoria University, Digital Solutions, Level 8 Rankin Brown Building, Wellington, NZ 6012 0064 4 463 6272

2 1

Slurm versions 24.11.5, 24.05.8, and 23.11.11 are now available (CVE-2025-43904)
by Tim Wickberg 07 May '25

07 May '25

Slurm versions 24.11.5, 24.05.8, and 23.11.11 are now available and include a fix for a recently discovered security issue. SchedMD customers were informed on April 23rd and provided a patch on request; this process is documented in our security policy. [1] A mistake with permission handling for Coordinators within Slurm's accounting system can allow a Coordinator to promote a user to Administrator. (CVE-2025-43904) Thank you to Sekou Diakite (HPE) for reporting this. Downloads are available at https://www.schedmd.com/downloads.php . Release notes follow below. - Tim [1] https://www.schedmd.com/security-policy/ -- Tim Wickberg Chief Technology Officer, SchedMD LLC Commercial Slurm Development and Support > * Changes in Slurm 24.11.5 > ========================== > -- Return error to scontrol reboot on bad nodelists. > -- slurmrestd - Report an error when QOS resolution fails for v0.0.40 > endpoints. > -- slurmrestd - Report an error when QOS resolution fails for v0.0.41 > endpoints. > -- slurmrestd - Report an error when QOS resolution fails for v0.0.42 > endpoints. > -- data_parser/v0.0.42 - Added +inline_enums flag which modifies the > output when generating OpenAPI specification. It causes enum arrays to not > be defined in their own schema with references ($ref) to them. Instead they > will be dumped inline. > -- Fix binding error with tres-bind map/mask on partial node allocations. > -- Fix stepmgr enabled steps being able to request features. > -- Reject step creation if requested feature is not available in job. > -- slurmd - Restrict listening for new incoming RPC requests further into > startup. > -- slurmd - Avoid auth/slurm related hangs of CLI commands during startup > and shutdown. > -- slurmctld - Restrict processing new incoming RPC requests further into > startup. Stop processing requests sooner during shutdown. > -- slurmcltd - Avoid auth/slurm related hangs of CLI commands during > startup and shutdown. > -- slurmctld: Avoid race condition during shutdown or reconfigure that > could result in a crash due delayed processing of a connection while > plugins are unloaded. > -- Fix small memleak when getting the job list from the database. > -- Fix incorrect printing of % escape characters when printing stdio > fields for jobs. > -- Fix padding parsing when printing stdio fields for jobs. > -- Fix printing %A array job id when expanding patterns. > -- Fix reservations causing jobs to be held for Bad Constraints > -- switch/hpe_slingshot - Prevent potential segfault on failed curl > request to the fabric manager. > -- Fix printing incorrect array job id when expanding stdio file names. > The %A will now be substituted by the correct value. > -- Fix printing incorrect array job id when expanding stdio file names. > The %A will now be substituted by the correct value. > -- switch/hpe_slingshot - Fix vni range not updating on slurmctld restart > or reconfigre. > -- Fix steps not being created when using certain combinations of -c and > -n inferior to the jobs requested resources, when using stepmgr and nodes > are configured with CPUs == Sockets*CoresPerSocket. > -- Permit configuring the number of retry attempts to destroy CXI service > via the new destroy_retries SwitchParameter. > -- Do not reset memory.high and memory.swap.max in slurmd startup or > reconfigure as we are never really touching this in slurmd. > -- Fix reconfigure failure of slurmd when it has been started manually and > the CoreSpecLimits have been removed from slurm.conf. > -- Set or reset CoreSpec limits when slurmd is reconfigured and it was > started with systemd. > -- switch/hpe-slingshot - Make sure the slurmctld can free step VNIs after > the controller restarts or reconfigures while the job is running. > -- Fix backup slurmctld failure on 2nd takeover. > -- Testsuite - fix python test 130_2. > -- Fix security issue where a coordinator could add a user with elevated > privileges. CVE-2025-43904. > * Changes in Slurm 24.05.8 > ========================== > -- Testsuite - fix python test 130_2. > -- Fix security issue where a coordinator could add a user with elevated > privileges. CVE-2025-43904. > * Changes in Slurm 23.11.11 > =========================== > -- Fixed a job requeuing issue that merged job entries into the same SLUID > when all nodes in a job failed simultaneously. > -- Add ABORT_ON_FATAL environment variable to capture a backtrace from any > fatal() message. > -- Testsuite - fix python test 130_2. > -- Fix security issue where a coordinator could add a user with elevated > privileges. CVE-2025-43904.

1 0

Lots of RPC calls and REQUEST_GETPW calls
by Guillette, Jeremy 07 May '25

07 May '25

Hello, I’m trying to figure out why we’ve been seeing an increase in network traffic in our AWS-based cluster, which uses Amazon’s parallel cluster tool. After an incident a couple weeks ago, I turned on debug2 logging on the slurmd processes, and I’m seeing huge numbers of `REQUEST_GETPW` and `REQUEST_GETGR` requests going to the slurmd processes. I briefly turned on debug2 logging for `slurmctld` as well, and I’m seeing lots of RPC calls, but not as many as the `REQUEST_GETPW` requests that I’ve seen on compute node slurmd processes. Here’s a sample from the slurmctld log: ``` [2025-04-28T15:11:05.436] debug2: _slurm_rpc_dump_partitions, size=1253 usec=20 [2025-04-28T15:11:05.450] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=2971 [2025-04-28T15:11:05.451] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=2971 [2025-04-28T15:11:05.451] debug2: _slurm_rpc_dump_partitions, size=1253 usec=16 [2025-04-28T15:11:05.461] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=2788 [2025-04-28T15:11:05.461] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=2788 [2025-04-28T15:11:05.461] debug2: _slurm_rpc_dump_partitions, size=1253 usec=12 [2025-04-28T15:11:05.517] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=2916 [2025-04-28T15:11:05.518] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=2916 [2025-04-28T15:11:05.518] debug2: _slurm_rpc_dump_partitions, size=1253 usec=14 [2025-04-28T15:11:05.628] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=3405 [2025-04-28T15:11:05.629] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=3405 [2025-04-28T15:11:05.629] debug2: _slurm_rpc_dump_partitions, size=1253 usec=14 [2025-04-28T15:11:05.740] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=2189 [2025-04-28T15:11:05.740] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=2189 [2025-04-28T15:11:05.740] debug2: _slurm_rpc_dump_partitions, size=1253 usec=15 [2025-04-28T15:11:05.845] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=2209 [2025-04-28T15:11:05.846] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=2209 [2025-04-28T15:11:05.846] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=4106 [2025-04-28T15:11:05.846] debug2: _slurm_rpc_dump_partitions, size=1253 usec=14 [2025-04-28T15:11:05.847] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=4106 [2025-04-28T15:11:05.847] debug2: _slurm_rpc_dump_partitions, size=1253 usec=11 [2025-04-28T15:11:05.938] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=3400 [2025-04-28T15:11:05.938] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=3400 [2025-04-28T15:11:05.938] debug2: _slurm_rpc_dump_partitions, size=1253 usec=18 [2025-04-28T15:11:06.903] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=3449 [2025-04-28T15:11:06.904] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=3449 [2025-04-28T15:11:06.904] debug2: _slurm_rpc_dump_partitions, size=1253 usec=15 [2025-04-28T15:11:07.175] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=3722 [2025-04-28T15:11:07.176] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=3722 [2025-04-28T15:11:07.177] debug2: _slurm_rpc_dump_partitions, size=1253 usec=254 [2025-04-28T15:11:07.205] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=4040 [2025-04-28T15:11:07.206] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=4040 [2025-04-28T15:11:07.206] debug2: _slurm_rpc_dump_partitions, size=1253 usec=17 [2025-04-28T15:11:07.237] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=2990 [2025-04-28T15:11:07.238] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=2990 [2025-04-28T15:11:07.239] debug2: _slurm_rpc_dump_partitions, size=1253 usec=15 [2025-04-28T15:11:07.284] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=2920 [2025-04-28T15:11:07.285] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=2920 [2025-04-28T15:11:07.285] debug2: _slurm_rpc_dump_partitions, size=1253 usec=15 [2025-04-28T15:11:07.370] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=3236 [2025-04-28T15:11:07.371] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=3236 [2025-04-28T15:11:07.371] debug2: _slurm_rpc_dump_partitions, size=1253 usec=17 [2025-04-28T15:11:08.463] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=2848 [2025-04-28T15:11:08.464] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=2848 [2025-04-28T15:11:08.464] debug2: _slurm_rpc_dump_partitions, size=1253 usec=14 [2025-04-28T15:11:08.691] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=2627 [2025-04-28T15:11:08.692] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=2627 [2025-04-28T15:11:08.692] debug2: _slurm_rpc_dump_partitions, size=1253 usec=18 [2025-04-28T15:11:08.873] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=3729 [2025-04-28T15:11:08.874] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=3729 [2025-04-28T15:11:08.875] debug2: _slurm_rpc_dump_partitions, size=1253 usec=196 [2025-04-28T15:11:08.881] debug2: Processing RPC: REQUEST_JOB_INFO_SINGLE from UID=3461 [2025-04-28T15:11:08.882] debug2: Processing RPC: REQUEST_PARTITION_INFO from UID=3461 [2025-04-28T15:11:08.882] debug2: _slurm_rpc_dump_partitions, size=1253 usec=10 ``` And from slurmd: ``` [2025-04-27T19:45:01.353] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:02.475] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:02.491] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:02.496] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:02.496] [59253.batch] debug: Handling REQUEST_GETGR [2025-04-27T19:45:02.497] [59253.batch] debug: Handling REQUEST_GETGR [2025-04-27T19:45:02.497] [59253.batch] debug: Handling REQUEST_GETGR [2025-04-27T19:45:02.501] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:02.504] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:02.507] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:02.513] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:02.518] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:02.518] [59253.batch] debug: Handling REQUEST_GETGR [2025-04-27T19:45:02.606] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:02.607] [59253.batch] debug: Handling REQUEST_GETGR [2025-04-27T19:45:04.988] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:04.992] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:04.995] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:04.999] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.011] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.016] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.033] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.045] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.048] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.057] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.073] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.077] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.110] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.143] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.143] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.144] [59253.batch] debug: Handling REQUEST_GETGR [2025-04-27T19:45:05.152] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.152] [59253.batch] debug: Handling REQUEST_GETGR [2025-04-27T19:45:05.159] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.159] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.159] [59253.batch] debug: Handling REQUEST_GETGR [2025-04-27T19:45:05.167] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.167] [59253.batch] debug: Handling REQUEST_GETGR [2025-04-27T19:45:05.170] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.172] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.174] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.203] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.204] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.207] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.316] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.318] [59253.batch] debug: Handling REQUEST_GETPW [2025-04-27T19:45:05.321] [59253.batch] debug: Handling REQUEST_GETPW ``` This level of debugging makes the logs pretty huge, but if seeing a whole log file is helpful, I can make something available. Any ideas on next steps for figuring out what’s going on? It seems like something is asking for authentication a whole lot, but it’s not clear to me what or why. We do use munge for Slurm authentication, and SSSD to work with LDAP for user authentication. -Jeremy Guillette — Jeremy Guillette Software Engineer, FAS Academic Technology | Academic Technology Harvard University Information Technology P: (617) 998-1826 | W: huit.harvard.edu (he/him/his)

4 6

Large memory jobs stuck Pending. Should use --time parameter?
by Mike 07 May '25

07 May '25

Greetings, We are new to Slurm and we are trying to better understand why we’re seeing high-mem jobs stuck in Pending state indefinitely. Smaller (mem) jobs in the queue will continue to pass by the high mem jobs even when we bump priority on a pending high-mem job way up. We have been reading over the backfill scheduling page and what we think we're seeing is that we need to require that users specify a --time parameter on their jobs so that Backfill works properly. None of our users specify a --time param because we have never required it. Is that what we need to require in order to fix this situation? From the backfill page: "Backfill scheduling is difficult without reasonable time limit estimates for jobs, but some configuration parameters that can help" and it goes on to list some config params that we have not set (DefaultTime, MaxTime, OverTimeLimit). We also see language such as, “Since the expected start time of pending jobs depends upon the expected completion time of running jobs, reasonably accurate time limits are important for backfill scheduling to work well.” So we suspect that we can achieve proper backfill scheduling by requiring that all users supply a "--time" parameter via a job submit plugin. Would that be a fair statement? Thank you in advance! -Mike Schor

4 4

Trying to using PMIx via srun for openmpi + pmix 5.0.7, PMIX ERROR: PMIX_ERR_FILE_OPEN_FAILURE in file gds_shmem2.c at line 1056 (but works with --mpi=pmix_v3?!)
by Dr. Thomas Orgis 06 May '25

06 May '25

Dear Slurm community, I am confused by the behaviour of a freshly built openmpi-5.0.7 with slurm-24.11.4. I can run a simple hello-world program via mpirun, but with really slow startup (a single process needing 1.6 s, 384 processes on two 192-core nodes need around half a minute). I guess there is a deeper issue here to work out with openmpi itself and why it needs 1.3 seconds to start a single process, even, outside a Slurm environment. So I investigate if running via srun changes things. Open-MPI docs recommend using mpirun and that has been traditionally our safe bet. But srun direct launch is supposed to work, too. I did duly build slurm-24.11.4 with ./configure --prefix=/syssw/slurm/24.11.4 \ --sysconfdir=/syssw/etc/slurm \ --with-munge=/syssw/munge/0.5.16 \ --with-hwloc=/syssw/hwloc/2.11.2 \ --disable-static --with-json \ --with-pmix=/syssw/pmix/3.2.5:/syssw/pmix/5.0.7 \ LDFLAGS=-Wl,--disable-new-dtags providing the two versions of pmix on our system currently. Now I am perplexed to observe that $ srun -vv --mpi=pmix_v5 -N 1 -n 1 mpihello does _not_ work, but produces c$ srun -vv -n 1 -N 1 --mpi=pmix_v5 mpihello srun: defined options srun: -------------------- -------------------- srun: (null) : n[164-165] srun: jobid : 671133 srun: job-name : interactive srun: mpi : pmix_v5 srun: nodes : 1 srun: ntasks : 1 srun: verbose : 2 srun: -------------------- -------------------- srun: end of defined options srun: debug: propagating SLURM_PRIO_PROCESS=0 srun: debug: propagating UMASK=0022 srun: jobid 671133: nodes(2):`n[164-165]', cpu counts: 192(x2) srun: debug: requesting job 671133, user 99, nodes 1 including ((null)) srun: debug: cpus 1, tasks 1, name mpihello, relative 65534 srun: CpuBindType=none srun: debug: Entering slurm_step_launch srun: debug: mpi/pmix_v5: pmixp_abort_agent_start: (null) [0]: pmixp_agent.c:417: Abort agent port: 36505 srun: debug: mpi/pmix_v5: _pmix_abort_thread: (null) [0]: pmixp_agent.c:356: Start abort thread srun: debug: mpi/pmix_v5: mpi_p_client_prelaunch: (null) [0]: mpi_pmix.c:282: setup process mapping in srun srun: debug: Entering _msg_thr_create() srun: debug: initialized stdio listening socket, port 38681 srun: debug: Started IO server thread srun: debug: Entering _launch_tasks srun: launching StepId=671133.3 on host n165, 1 tasks: 0 srun: topology/tree: init: topology tree plugin loaded srun: debug: launch returned msg_rc=0 err=0 type=8001 srun: Node n165, 1 tasks started [n165:2287661] PMIX ERROR: PMIX_ERR_FILE_OPEN_FAILURE in file gds_shmem2.c at line 1056 *** An error occurred in MPI_Init *** on a NULL communicator *** MPI_ERRORS_ARE_FATAL (processes in this communicator will now abort, *** and MPI will try to terminate your MPI job as well) [n165:2287661] Local abort before MPI_INIT completed completed successfully, but am not able to aggregate error messages, and not able to guarantee that all other processes were killed! srun: Received task exit notification for 1 task of StepId=671133.3 (status=0x0e00). srun: error: n165: task 0: Exited with exit code 14 srun: debug: task 0 done srun: debug: IO thread exiting srun: debug: mpi/pmix_v5: _conn_readable: (null) [0]: pmixp_agent.c:109: false, shutdown srun: debug: mpi/pmix_v5: _pmix_abort_thread: (null) [0]: pmixp_agent.c:363: Abort thread exit Observe the line [n165:2287661] PMIX ERROR: PMIX_ERR_FILE_OPEN_FAILURE in file gds_shmem2.c at line 1056 anyone got an idea what that means, by what it's caused? And, what really confuses me, is that the test program _does_ work if I switch from pmix_v5 to pmix_v3: $ srun -vv -n 1 -N 1 --mpi=pmix_v3 mpihello srun: defined options srun: -------------------- -------------------- srun: (null) : n[164-165] srun: jobid : 671133 srun: job-name : interactive srun: mpi : pmix_v3 srun: nodes : 1 srun: ntasks : 1 srun: verbose : 2 srun: -------------------- -------------------- srun: end of defined options srun: debug: propagating SLURM_PRIO_PROCESS=0 srun: debug: propagating UMASK=0022 srun: jobid 671133: nodes(2):`n[164-165]', cpu counts: 192(x2) srun: debug: requesting job 671133, user 99, nodes 1 including ((null)) srun: debug: cpus 1, tasks 1, name mpihello, relative 65534 srun: CpuBindType=none srun: debug: Entering slurm_step_launch srun: debug: mpi/pmix_v3: pmixp_abort_agent_start: (null) [0]: pmixp_agent.c:417: Abort agent port: 43737 srun: debug: mpi/pmix_v3: _pmix_abort_thread: (null) [0]: pmixp_agent.c:356: Start abort thread srun: debug: mpi/pmix_v3: mpi_p_client_prelaunch: (null) [0]: mpi_pmix.c:282: setup process mapping in srun srun: debug: Entering _msg_thr_create() srun: debug: initialized stdio listening socket, port 43805 srun: debug: Started IO server thread srun: debug: Entering _launch_tasks srun: launching StepId=671133.4 on host n164, 1 tasks: 0 srun: topology/tree: init: topology tree plugin loaded srun: debug: launch returned msg_rc=0 err=0 type=8001 srun: Node n164, 1 tasks started hello world from processor n164, rank 0 out of 1 srun: Received task exit notification for 1 task of StepId=671133.4 (status=0x0000). srun: n164: task 0: Completed srun: debug: task 0 done srun: debug: IO thread exiting srun: debug: mpi/pmix_v3: _conn_readable: (null) [0]: pmixp_agent.c:109: false, shutdown srun: debug: mpi/pmix_v3: _pmix_abort_thread: (null) [0]: pmixp_agent.c:363: Abort thread exit How can a PMIx 5 MPI even work with the pmix_v3 plugin? Why does it _not_ work with the pmix_v5 plugin? I am also curious why the plugins don't link to the respective libpmix (are they using dlopen for their dependencies? Why?). $ ldd /syssw/slurm/24.11.4/lib/slurm/mpi_pmix*.so /syssw/slurm/24.11.4/lib/slurm/mpi_pmix.so: linux-vdso.so.1 (0x00007ffd19ffb000) libhwloc.so.15 => /syssw/hwloc/2.11.2/lib/libhwloc.so.15 (0x000014d199e56000) libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x000014d199c70000) libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x000014d199b90000) /lib64/ld-linux-x86-64.so.2 (0x000014d199edd000) /syssw/slurm/24.11.4/lib/slurm/mpi_pmix_v3.so: linux-vdso.so.1 (0x00007ffd265f2000) libhwloc.so.15 => /syssw/hwloc/2.11.2/lib/libhwloc.so.15 (0x00001553902c8000) libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00001553900e2000) libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x0000155390002000) /lib64/ld-linux-x86-64.so.2 (0x0000155390350000) /syssw/slurm/24.11.4/lib/slurm/mpi_pmix_v5.so: linux-vdso.so.1 (0x00007ffd862b7000) libhwloc.so.15 => /syssw/hwloc/2.11.2/lib/libhwloc.so.15 (0x0000145adc36d000) libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x0000145adc187000) libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x0000145adc0a7000) /lib64/ld-linux-x86-64.so.2 (0x0000145adc3f4000) But they do have the proper RPATH set up: $ readelf -d /syssw/slurm/24.11.4/lib/slurm/mpi_pmix*.so | grep -e ^File -e PATH File: /syssw/slurm/24.11.4/lib/slurm/mpi_pmix.so 0x000000000000000f (RPATH) Library rpath: [/syssw/hwloc/2.11.2/lib:/syssw/pmix/5.0.7/lib] File: /syssw/slurm/24.11.4/lib/slurm/mpi_pmix_v3.so 0x000000000000000f (RPATH) Library rpath: [/syssw/hwloc/2.11.2/lib:/syssw/pmix/3.2.5/lib] File: /syssw/slurm/24.11.4/lib/slurm/mpi_pmix_v5.so 0x000000000000000f (RPATH) Library rpath: [/syssw/hwloc/2.11.2/lib:/syssw/pmix/5.0.7/lib] Which is important, since libpmix doesn't get sensible SONAME versioning (supposing they are supposed to be separate ABIs): $ find /syssw/pmix/* -name 'libpmix.so*' /syssw/pmix/3.2.5/lib/libpmix.so /syssw/pmix/3.2.5/lib/libpmix.so.2.2.35 /syssw/pmix/3.2.5/lib/libpmix.so.2 /syssw/pmix/5.0.7/lib/libpmix.so /syssw/pmix/5.0.7/lib/libpmix.so.2.13.7 /syssw/pmix/5.0.7/lib/libpmix.so.2 It's all libpmix.so.2. My mpihello program uses the 5.0.7 one, at least: $ ldd mpihello linux-vdso.so.1 (0x00007fff1f13f000) libmpi.so.40 => /sw/env/gcc-13.3.0/openmpi/5.0.7/lib/libmpi.so.40 (0x000014ed89d95000) libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x000014ed89baf000) libopen-pal.so.80 => /sw/env/gcc-13.3.0/openmpi/5.0.7/lib/libopen-pal.so.80 (0x000014ed89a25000) libfabric.so.1 => /syssw/fabric/1.21.0/lib/libfabric.so.1 (0x000014ed8989b000) libefa.so.1 => /lib/x86_64-linux-gnu/libefa.so.1 (0x000014ed8988d000) libibverbs.so.1 => /lib/x86_64-linux-gnu/libibverbs.so.1 (0x000014ed8986c000) libpsm2.so.2 => /syssw/psm2/12.0.1/lib/libpsm2.so.2 (0x000014ed89804000) libatomic.so.1 => /sw/compiler/gcc-13.3.0/lib64/libatomic.so.1 (0x000014ed897fb000) libnl-route-3.so.200 => /lib/x86_64-linux-gnu/libnl-route-3.so.200 (0x000014ed8976a000) libnl-3.so.200 => /lib/x86_64-linux-gnu/libnl-3.so.200 (0x000014ed89745000) libpmix.so.2 => /syssw/pmix/5.0.7/lib/libpmix.so.2 (0x000014ed8951e000) libevent_core-2.1.so.7 => /lib/x86_64-linux-gnu/libevent_core-2.1.so.7 (0x000014ed894e8000) libevent_pthreads-2.1.so.7 => /lib/x86_64-linux-gnu/libevent_pthreads-2.1.so.7 (0x000014ed894e3000) libhwloc.so.15 => /syssw/hwloc/2.11.2/lib/libhwloc.so.15 (0x000014ed89486000) libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x000014ed893a6000) /lib64/ld-linux-x86-64.so.2 (0x000014ed8a0d8000) libnuma.so.1 => /lib/x86_64-linux-gnu/libnuma.so.1 (0x000014ed89397000) Can someone shed light on how the differing PMIx plugins are supposed to work? Can someone share a setup where pmix_v5 does work with openmpi 5.x? Alrighty then, Thomas -- Dr. Thomas Orgis HPC @ Universität Hamburg

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knl_generic.conf seems to be ignored and Slurm adopts default settings which specify Intel motherboard and syscfg - need help to figure out why Slurm is not reading my Dell knl_generic.conf parameters
by Bryan Johnston 01 May '25

01 May '25

Hi folks I'm in the process of standing up some Stampede2 Dell C3620p KNL nodes and I seem to be hitting a blind spot. I previously "successfully" configured KNL's on an Intel board (S7200AP), with OpenHPC and Rocky8. I say "successfully" because it works but evidently my latest troubleshooting has revealed that I may have been lucky rather than an expert KNL integrator :-) I thought I knew what I was doing, but after repeating my Intel KNL recipe with the Dell system, I have unearthed my ignorance with this wonderful (but deprecated) technology (anecdotally, the KNLs offer excellent performance and power efficiency for our workloads, particularly when contrasted with our alternative available hardware). The first discovery was the "syscfg" for Intel boards is not the same as the "syscfg" for Dell boards. I've since sorted this out. The second discovery was made while troubleshooting an issue that I'm hitting. After realising that the slurmd client nodes don't seem to be reading the "knl_generic.conf" parameters that are specified in /etc/slurm on the smshost (OpenHPC parlance for head node ... And it's a Slurm config less set up), I think my original Intel solution was working out of luck more than ingenuity. For reference , the Slurm configuration for KNL now includes: ``` NodeFeaturesPlugins=knl_generic DebugFlags=NodeFeatures GresTypes=hbm ``` And I've created a separate "knl_generic.conf" that points to the Dell specific tools and features. For the Dell system, slurmd seems to ignore my knl_generic.conf file and is drawing defaults from somewhere else. Slurm still considers SystemType to be Intel, SyscfgPath to be the default location, and SyscfgTimeout to be 1000. For Dell systems, Slurm needs to have SystemType=Dell and Timeout to be 1000. I don't understand why the nodes are not reading the knl_generic file - any help or clues would be appreciated. Here's my theory on what is happening: The Intel KNL system was successful by luck ... It probably exhibited the same ignore-the-config-file but ran default NodeFeatures for some generic knl_generic settings which are stored somewhere as default parameters. I must have just lucked out when I was using my Intel KNL system because it was using the defaults (that are compatible with Intel). If this assumption is correct, the Dell system is not working because it isn't compatible with the Intel defaults. Any clues on how to successfully invoke the config file (or better debuggingtechniwues to figure out why it isn't) would be appreciated. I can share journalctl feedback if necessary. For now, I've tried changing ownership of the config files to root:slurm, copied knl_generic.conf to the compute nodes' /etc/slurm/ and also tried to specify the config file by running (on the compute nodes) "slurmd" with "-f" ... No joy; if slurmd runs successfully (when I don't screw up some random experimental settings) then it always seems to ignore knl_generic.conf and loads some default settings from somewhere. A few questions: 1. Are there default settings stored somewhere? I might be barking up the wrong tree, although I've looked for files that may clash with the config file I've created but can't find any. 2. Is there a better way to force the knl_generic file to be loaded? 3. Is the configless Slurm somehow not reading the knl_generic file to the clients? I understand that all configuration files are read from the host server. Many thanks for any help! Regards / Groete / Sala(ni) Kahle - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Bryan Johnston Senior HPC Technologist II Lead: HPC Ecosystems Project HPCwire 2024's Outstanding Leader in HPC CHPC | www.chpc.ac.za | NICIS | nicis.ac.za Centre for High Performance Computing If you receive an email from me out of office hours for you, please do not feel obliged to respond during off-hours! Book time to meet with me<https://outlook.office.com/bookwithme/user/87af4906a703488386578f34e4473c74…>

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Slurm and Kerberos/GSSAPI
by Burian, John 01 May '25

01 May '25

Does anyone have any experience with using Kerberos/GSSAPI and Slurm? I’m specifically wondering if there is a known mechanism for providing proper Kerberos credentials to Slurm batch jobs, such that those processes would be able to access a filesystem that requires Kerberos credentials. Some quick searching returned nothing useful. Interactive jobs have a similar problem, but I’m hoping that SSH credential forwarding can be leveraged there. I’m nothing like an expert in Kerberos, so forgive any apparent ignorance. Thanks, John

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