<html>
<head>
<meta http-equiv="Content-Type" content="text/html;
charset=windows-1252">
</head>
<body>
<p>I would look at:</p>
<dl compact="compact">
<dt><i>MaxJobs</i>=<max jobs></dt>
<dd>
Maximum number of jobs each user is allowed to run at one time
in this
association.
This is overridden if set directly on a user.
Default is the cluster's limit.
To clear a previously set value use the modify command with a
new value of -1.
</dd>
</dl>
<p>Which is Association based. So you could just modify their
account directly and set it to something low.</p>
<p>You can also simply put their pending jobs in hold state. That
way they won't be considered for scheduling but won't be outright
removed. Setting fairshare to 0 has the same effect.</p>
<p>-Paul Edmon-<br>
</p>
<div class="moz-cite-prefix">On 9/22/2020 7:58 PM, Brian Andrus
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:00c34c3f-813d-e5c8-2fb2-00d2bcf8680a@gmail.com">
<meta http-equiv="Content-Type" content="text/html;
charset=windows-1252">
<p>Well, I know of no way to 'throttle' running jobs. Once they
are out the gate, you can't stop them from leaving..</p>
<p>That said, your approach of setting arraytaskthrottle is just
what you want for any pending jobs.</p>
<p>As a preventative measure, I imagine you could set the default
to 1 and then change it with a job_submit script.</p>
<p>As far as currently running tasks, well, you have to figure
that. You could kill/requeue them, but that can break things for
the user. If their code supports it, they could
checkpoint/restart as part of the process.</p>
<p>You can suspend them, but they still sit on the node waiting to
be resumed, but the node resources may get assigned to other
jobs while they wait to resume.</p>
<p>Brian Andrus<br>
</p>
<p><br>
</p>
<div class="moz-cite-prefix">On 9/22/2020 2:33 PM, Ransom,
Geoffrey M. wrote:<br>
</div>
<blockquote type="cite"
cite="mid:90d1ce76fe814f9eafd588c56cee577c@APLEX03.dom1.jhuapl.edu">
<meta http-equiv="Content-Type" content="text/html;
charset=windows-1252">
<meta name="Generator" content="Microsoft Word 15 (filtered
medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-serif;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:#0563C1;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:#954F72;
text-decoration:underline;}
p.MsoListParagraph, li.MsoListParagraph, div.MsoListParagraph
{mso-style-priority:34;
margin-top:0in;
margin-right:0in;
margin-bottom:0in;
margin-left:.5in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-serif;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Calibri",sans-serif;
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri",sans-serif;}size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
ol
{margin-bottom:0in;}
ul
{margin-bottom:0in;}</style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
<div class="WordSection1">
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Hello<o:p></o:p></p>
<p class="MsoNormal"> We had a user post a large number of
array jobs with a short actual run time (20-80 seconds, but
mostly to the low end) and slurmctld was falling behind on
RPC calls trying to handle the jobs. It was a bit awkward
trying to slap arraytaskthrottle=5 on each of the queued
array jobs while slurmctld was having issues handling the
RPC load.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m looking to make a QOS with
MaxJobsPerUser=50 set that I can quickly add to a user to
throttle their jobs but..<o:p></o:p></p>
<p class="MsoListParagraph"
style="text-indent:-.25in;mso-list:l0 level1 lfo1"><!--[if !supportLists]--><span
style="mso-list:Ignore">1)<span style="font:7.0pt
"Times New Roman""> </span></span><!--[endif]-->Adding
a QOS to the user does not affect queued jobs so I still
have to get all of the users jobids and modify each on
directly.<o:p></o:p></p>
<p class="MsoListParagraph"
style="text-indent:-.25in;mso-list:l0 level1 lfo1"><!--[if !supportLists]--><span
style="mso-list:Ignore">2)<span style="font:7.0pt
"Times New Roman""> </span></span><!--[endif]-->I
queued up a test job with the QOS set and it is still
running 100 jobs at a time (what I set arraytaskthrottle to
in the job) and not limiting the “user” to 50 jobs.<o:p></o:p></p>
<p class="MsoListParagraph"
style="text-indent:-.25in;mso-list:l0 level1 lfo1"><!--[if !supportLists]--><span
style="mso-list:Ignore">3)<span style="font:7.0pt
"Times New Roman""> </span></span><!--[endif]-->I
tried adding the FLAG OverPartQOS to see if that changed the
behavior, but it did not seem to do anything. My test
cluster I ran this on doesn’t have any other QOSes defined
but our production cluster does have a partition QOS in
place limiting single users to about 80% of the CPUs with
MaxTRESPerUser.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is there a quick way to limit how many
jobs a specific user can run at one time on the cluster or
in a partition if we need to throttle them back in an
emergency but we don’t want to flat out kill their jobs?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks. <o:p></o:p></p>
</div>
</blockquote>
</blockquote>
</body>
</html>