Check if mysql is using multithreading?

Question

When I check the processes/active tasks on centos using the top command, when using SSH. I only see 1 mysql process. Does this mean that it is only using one cpu core out of my 4 cpu cores?

`top` doesn't show threads, it shows processes. – EEAA Sep 24 '13 at 20:20 — EEAA, Sep 24 '13 at 20:20
@EEAA so, your suggestion is.... – user8005 Sep 24 '13 at 20:21 — user8005, Sep 24 '13 at 20:21

score 1 · Answer 1 · answered Sep 24 '13 at 20:24

1

Mysql is definitely a multithreaded application, and has no option to 'disable multithreading', whatever that would mean. A tool like htop will show you individual threads, as will looking in /proc/:

dennis@lightning:~$ ls  /proc/$(pidof mysqld)/task/ | wc -l
17

The task/ directory for a process contains one entry per thread. Mysql on this bix is currently thus using 17 threads.

answered Sep 24 '13 at 20:24

Dennis Kaarsemaker

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htop: command not found – user8005 Sep 24 '13 at 20:29
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@user8005 - so *install* it. – EEAA Sep 24 '13 at 20:39
htop only shows one process. – user8005 Sep 24 '13 at 21:01
Does this mean that it is only using one cpu core out of my 4 cpu cores? – user8005 Sep 24 '13 at 21:31
That means your htop is behaving differently than mine. How many subdirs are there in /proc/$(pidof mysqld)/task ? – Dennis Kaarsemaker Sep 25 '13 at 01:38

Check if mysql is using multithreading?

1 Answers1