{"version":"1.0","provider_name":"UCT HPC","provider_url":"https:\/\/ucthpc.uct.ac.za","author_name":"Andrew Lewis","author_url":"https:\/\/ucthpc.uct.ac.za\/index.php\/author\/andrew-lewis\/","title":"SLURM and memory management - UCT HPC","type":"rich","width":600,"height":338,"html":"<blockquote class=\"wp-embedded-content\" data-secret=\"uut29HdWZB\"><a href=\"https:\/\/ucthpc.uct.ac.za\/index.php\/2015\/06\/26\/slurm-and-memory-management\/\">SLURM and memory management<\/a><\/blockquote><iframe sandbox=\"allow-scripts\" security=\"restricted\" src=\"https:\/\/ucthpc.uct.ac.za\/index.php\/2015\/06\/26\/slurm-and-memory-management\/embed\/#?secret=uut29HdWZB\" width=\"600\" height=\"338\" title=\"&#8220;SLURM and memory management&#8221; &#8212; UCT HPC\" data-secret=\"uut29HdWZB\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\" class=\"wp-embedded-content\"><\/iframe><script type=\"text\/javascript\">\n\/*! This file is auto-generated *\/\n!function(c,d){\"use strict\";var e=!1,o=!1;if(d.querySelector)if(c.addEventListener)e=!0;if(c.wp=c.wp||{},c.wp.receiveEmbedMessage);else if(c.wp.receiveEmbedMessage=function(e){var t=e.data;if(!t);else if(!(t.secret||t.message||t.value));else if(\/[^a-zA-Z0-9]\/.test(t.secret));else{for(var r,s,a,i=d.querySelectorAll('iframe[data-secret=\"'+t.secret+'\"]'),n=d.querySelectorAll('blockquote[data-secret=\"'+t.secret+'\"]'),o=new RegExp(\"^https?:$\",\"i\"),l=0;l<n.length;l++)n[l].style.display=\"none\";for(l=0;l<i.length;l++)if(r=i[l],e.source!==r.contentWindow);else{if(r.removeAttribute(\"style\"),\"height\"===t.message){if(1e3<(s=parseInt(t.value,10)))s=1e3;else if(~~s<200)s=200;r.height=s}if(\"link\"===t.message)if(s=d.createElement(\"a\"),a=d.createElement(\"a\"),s.href=r.getAttribute(\"src\"),a.href=t.value,!o.test(a.protocol));else if(a.host===s.host)if(d.activeElement===r)c.top.location.href=t.value}}},e)c.addEventListener(\"message\",c.wp.receiveEmbedMessage,!1),d.addEventListener(\"DOMContentLoaded\",t,!1),c.addEventListener(\"load\",t,!1);function t(){if(o);else{o=!0;for(var e,t,r,s=-1!==navigator.appVersion.indexOf(\"MSIE 10\"),a=!!navigator.userAgent.match(\/Trident.*rv:11\\.\/),i=d.querySelectorAll(\"iframe.wp-embedded-content\"),n=0;n<i.length;n++){if(!(r=(t=i[n]).getAttribute(\"data-secret\")))r=Math.random().toString(36).substr(2,10),t.src+=\"#?secret=\"+r,t.setAttribute(\"data-secret\",r);if(s||a)(e=t.cloneNode(!0)).removeAttribute(\"security\"),t.parentNode.replaceChild(e,t);t.contentWindow.postMessage({message:\"ready\",secret:r},\"*\")}}}}(window,document);\n<\/script>\n","description":"SLURM allows a DefMemPerCPU and a MaxMemPerCPU to be set. If a user does not set a memory limit the default will be used. This is normally set to MaxMem\/NumCores. As memory is a consumable resource (SelectTypeParameters=CR_Core_Memory) MaxMemPerCPU serves not only to protect the node's memory but will also automatically increase a job's core count on submission where possible. Below are 5 similar jobs submited by a user, each one requiring more memory. The nodes all have 2GB of RAM per core. The initial --ntasks (cores) of each job is set to 1. However as MaxMemPerCPU is set to 2GB the number of cores is increased by the scheduler to a of multiple of each 2GB or RAM requested.# &nbsp;JOBID &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; NAME &nbsp;USER CPUS &nbsp; &nbsp; &nbsp;NODELIST &nbsp; &nbsp; &nbsp;----------------------------------------------------------------------------1 &nbsp; 2043 &nbsp; &nbsp; &nbsp;Mem_Test_500M &nbsp; andy &nbsp; &nbsp; &nbsp; 1 &nbsp; &nbsp;srvcnthpc408 &nbsp; &nbsp;2 &nbsp; 2044 &nbsp; &nbsp;Mem_Test_2000M &nbsp; andy &nbsp; &nbsp; &nbsp; 1 &nbsp; &nbsp;srvcnthpc408 &nbsp; &nbsp;&nbsp;3 &nbsp; 2045 &nbsp; &nbsp;Mem_Test_5000M &nbsp; andy &nbsp; &nbsp; &nbsp; 3 &nbsp; &nbsp;srvcnthpc406 &nbsp; &nbsp;&nbsp;4 &nbsp; 2046 &nbsp; &nbsp;Mem_Test_8000M &nbsp; andy &nbsp; &nbsp; &nbsp; 4 &nbsp; &nbsp;srvcnthpc406 &nbsp; &nbsp;&nbsp;5 &nbsp; 2047 &nbsp;Mem_Test_10000M &nbsp; andy &nbsp; &nbsp; &nbsp; 5 &nbsp; &nbsp;srvcnthpc407 &nbsp;"}