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| − | Python, Linkers and Virtual Memory https://www.youtube.com/watch?v=twQKAoq2OPE | + | Python, Likers and Virtual Memory https://www.youtube.com/watch?v=twQKAoq2OPE |
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| − | Reporting on "actual" memory usage of your application with smem http://linuxaria.com/pills/linux-terminal-check-who-uses-all-your-memory-with-smem
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| − | ==Transparent Hugepages ==
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| − | * https://access.redhat.com/solutions/46111 for Fedora and RHEL Note: their commands at the end of the article for determining if HugePages are disabled do not work in my limited tests. I have both Ubuntu and CentOS systems which are using HugePages, yet <code>grep -i HugePages_Total /proc/meminfo</code> <code>cat /proc/sys/vm/nr_hugepages</code> and <code>sysctl vm.nr_hugepages</code> all report zero. Meanwhile <code>grep AnonHugePages /proc/meminfo</code> and <code>grep -e AnonHugePages /proc/*/smaps | awk '{ if($2>4) print $0} ' | awk -F "/" '{print $0; system("ps -fp " $3)} '</code> report actual usage. The biggest applications? [[mysql]]d, [[java]], [[python]], [[node]], polkitd, [[mongo]]d, [[httpd]]
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| − | Strangely, the value for <code>cat /sys/kernel/mm/transparent_hugepage/enabled</code>
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| − | <pre>[always] madvise never</pre>
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| − | Note that in order to enable or disable THP ''permanently'' (so that it survives reboots), you need to do more than just echo a value to <code>/sys/kernel/mm/transparent_hugepage/enabled</code>. And there are subtle differences between distros. <ref>https://askubuntu.com/questions/597372/how-do-i-modify-sys-kernel-mm-transparent-hugepage-enabled</ref>
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| | [[Category:System Administration]] | | [[Category:System Administration]] |
| − | [[Category:Memory]]
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| − | [[Category:Performance]]
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| − | [[Category:Kernel]]
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| − | [[Category:Configuration Management]]
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