https://www.fromdual.com/tags/system-time/Recent content in System Time on FromDual GmbHHugoen-GBoli.sennhauser@fromdual.com (Oli Sennhauser)oli.sennhauser@fromdual.com (Oli Sennhauser)© FromDual GmbHFri, 15 Mar 2019 18:26:49 +0000https://www.fromdual.com/blog/linux-system-calls-of-mysql-process/Fri, 15 Mar 2019 17:06:24 +0000oli.sennhauser@fromdual.com (Oli Sennhauser)https://www.fromdual.com/blog/linux-system-calls-of-mysql-process/<p>We had the problem today that a MySQL Galera Cluster node with the <a href="https://whatis.techtarget.com/definition/multi-tenancy" target="_blank" title="multi-tenancy">multi-tenancy</a> pattern caused a lot of <a href="https://en.wikipedia.org/wiki/Time_%28Unix%29#User_time_vs_system_time" target="_blank" title="User time vs system time">system time</a> (sy 75%, <a href="http://www.brendangregg.com/blog/2017-08-08/linux-load-averages.html" target="_blank" title="Linux Load Averages: Solving the Mystery">load average</a> about 30 (you really must read this article by Brendan Gregg, it is worth it!)) so we wanted to find what <a href="https://en.wikipedia.org/wiki/System_call" target="_blank" title="System call">system calls</a> are being used to see what could cause this issue (to verify if it is a <a href="https://www.fromdual.com/node/1306" title="Table open cache too small">TOC</a> or a <a href="https://www.fromdual.com/node/1305" title="Table definition cache too small">TDC</a> problem:</p>