this thread<\/a> gives the solution, namely calling Matlab with the -singleCompThread argument.\u00a0 In the process list we still noticed 2 threads but one was set to 'Sleep' while only one consumed actual CPU time.\u00a0 The designated CPU seemed to be static, in other words the thread did not jump from one CPU to another and the consumed resource via qstat and SNMP was consistent.\u00a0 Obviously from a user's perspective it is desirable to consume as many CPUs as possible, however a shared environment where the assignemnt of resources is removed from the scheduler will invariably lead to resource contention and overall performance degredation.","protected":false},"excerpt":{"rendered":"Over the past week we became aware of an issue with Matlab and its desire to consume as many CPUs as possible. This despite the fact that we were no longer running the parallel library. This thread<\/a> outlines the problem we were experiencing and this thread<\/a> gives the solution, namely calling Matlab with the -singleCompThread argument. In the process list we still noticed 2 threads but one was set to ‘Sleep’ while only one consumed actual CPU time. The designated CPU seemed to be static, in other words the thread did not jump from one CPU to another and the consumed resource via qstat and SNMP was consistent. Obviously from a user’s perspective it is desirable to consume as many CPUs as possible, however a shared environment where the assignemnt of resources is removed from the scheduler will invariably lead to resource contention and overall performance degredation.<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[9,4],"tags":[],"yoast_head":"\nMatlab on diet - UCT HPC<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/ucthpc.uct.ac.za\/index.php\/2011\/08\/02\/matlab-on-diet\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Matlab on diet - UCT HPC\" \/>\n<meta property=\"og:description\" content=\"Over the past week we became aware of an issue with Matlab and its desire to consume as many CPUs as possible. This despite the fact that we were no longer running the parallel library. This thread outlines the problem we were experiencing and this thread gives the solution, namely calling Matlab with the -singleCompThread argument. In the process list we still noticed 2 threads but one was set to 'Sleep' while only one consumed actual CPU time. The designated CPU seemed to be static, in other words the thread did not jump from one CPU to another and the consumed resource via qstat and SNMP was consistent. 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