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

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

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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

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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

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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

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Account getting duplicated
by Ratnasamy, Fritz 28 May '25

28 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

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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

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Crash in "slurmd -C" when latest NVIDIA drivers are used
by Taras Shapovalov 23 May '25

23 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

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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

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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

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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

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