{"id":1905,"date":"2015-06-18T22:54:30","date_gmt":"2015-06-19T05:54:30","guid":{"rendered":"http:\/\/blogs.reed.edu\/shusterman_lab\/?p=1905"},"modified":"2015-08-12T16:10:46","modified_gmt":"2015-08-12T23:10:46","slug":"out-of-memory-errors-in-spartan","status":"publish","type":"post","link":"https:\/\/blogs.reed.edu\/shusterman_lab\/2015\/06\/out-of-memory-errors-in-spartan\/","title":{"rendered":"‘Out of Memory’ Errors in Spartan"},"content":{"rendered":"

The computers in C203 are equipped with i7 8-core processors and 8G of total RAM. This occasionally leads to “out of memory” errors. These errors are particularly common during Spartan DFT IR calculations (a typical output error message reads, “Error Occurred: Not enough total memory”).<\/p>\n

The error occurs because of a mismatch between the available memory and Spartan’s expectations regarding memory. Spartan normally expects to use all 8 cores and to find 2G\/core, but not all Spartan calculations actually demand this much memory. When a Spartan calculation actually demands all of the expected memory, e.g., the situation that occurs in DFT IR calculations of a certain size, Spartan discovers that the memory it expects (16G total) exceeds the memory available (8G or less), and an “out of memory” error is the result.<\/p>\n

<\/p>\n

The solution is to reduce the total amount of RAM memory that Spartan will look for. This can be accomplished by reducing the number of cores that Spartan uses. Here are two different ways to set this up:<\/p>\n

    \n
  1. Automatic<\/strong><\/span> CPU allocation\n
      \n
    1. Open Options: Preferences: Jobs<\/strong> and select Automatic<\/strong>. Click OK<\/strong>.<\/li>\n
    2. Open Setup: Calculations<\/strong>, set the calculation parameters you require, and enter either CPUCNT=2<\/strong> or CPUCNT=3<\/strong> in the Options<\/strong> box. Click Submit<\/strong>.<\/li>\n<\/ol>\n<\/li>\n
    3. Manual<\/strong><\/span> CPU allocation\n
        \n
      1. Open Options: Preferences: Jobs<\/strong> and select Manual<\/strong>. Set the #Concurrent Molecules\/Job<\/strong> to 1 molecule<\/strong>. Set #Cores\/Molecule<\/strong> to either 2 cores<\/strong> or 3 cores<\/strong>. Click Expert<\/strong> and set Per Job Limits: Memory Limit<\/strong> to 6000 MB<\/strong> or less. Click OK<\/strong>.<\/li>\n
      2. Open Setup: Calculations<\/strong>, set the calculation parameters you require, and click Submit<\/strong>. (No special options are needed.)<\/li>\n<\/ol>\n<\/li>\n<\/ol>\n

        Either approach will reduce the total memory that Spartan expects to 6G or less. It is necessary to set Spartan’s memory allocation to substantially less than 8G because the Windows OS and user applications also require some of the available memory.<\/p>\n","protected":false},"excerpt":{"rendered":"

        The computers in C203 are equipped with i7 8-core processors and 8G of total RAM. This occasionally leads to “out of memory” errors. These errors are particularly common during Spartan DFT IR calculations (a typical output error message reads, “Error … finish reading ‘Out of Memory’ Errors in Spartan<\/a><\/p>\n","protected":false},"author":55,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[32,33,31,27],"class_list":["post-1905","post","type-post","status-publish","format-standard","hentry","category-spartan-howto","tag-cores","tag-cpus","tag-memory","tag-spartan"],"_links":{"self":[{"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/posts\/1905","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/users\/55"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/comments?post=1905"}],"version-history":[{"count":8,"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/posts\/1905\/revisions"}],"predecessor-version":[{"id":1917,"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/posts\/1905\/revisions\/1917"}],"wp:attachment":[{"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/media?parent=1905"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/categories?post=1905"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/tags?post=1905"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}