List:General Discussion« Previous MessageNext Message »
From:Jocelyn Fournier Date:July 4 2002 7:00am
Subject:Re: Growing memory usage/processes
View as plain text  
Hi,

Hi,

It depends also of how many threads are running at the same time + sort
buffer / record buffer values.
The memory consumption can be roughly calculated as key buffer + (sort
buffer + record buffer) * number of thread.
As you can see, only the key buffer is shared between all the threads.
If you want to lower the number of "sleeping" thread, take a look at the
wait_timeout variable in your my.cnf file.

Regards,
  Jocelyn
----- Original Message -----
From: "Dave" <dave@stripped>
To: <mysql@stripped>
Sent: Thursday, July 04, 2002 8:39 AM
Subject: Re: Growing memory usage/processes


> Thanks for the confirmation Dan,
>
> I will look a little closer but I could have sworn when I shutdown MySQL
> about 300MB of memory got freed.
>
> I had a suspicion the case was one process and ps/top could not
> distinguish...I just needed to hear confirmation of it I guess.
>
>
> -Dave
>
>
> > In the last episode (Jul 03), Dave said:
> > > Hello all,
> > >
> > > I have mysql running on a 2.4.18 kernel:
> > >
> > > /usr/libexec/mysqld  Ver 3.23.49 for redhat-linux-gnu on i386
> > >
> > > and note that one started about 4 processes (threads?) began to
> > > handle the various signal/table tasks and such. After several random
> > > queries the process list grows accordingly.
> > >
> > > After a couple hours all processes which showed consumption of about
> > > 8MB of memory initially are now 25MB each and growing as queries are
> > > received.
> > >
> > > My question is...Why if these are threads does it require each thread
> > > to utilize so much memory? 4 threads using 10MB each is ok, 10
> > > threads using 10MB each is ok. 20 threads using 25MB each is too
> > > much.
> >
> > No.  Threads share the same address space.  You are seeing one threaded
> > application consuming 25MB.  Linux's threads implentation creates a
> > separate process for each thread and top has no idea they're really all
> > one application.  Linux is the only OS that does this, afaik, and you
> > would not believe the number of times your question has been asked on
> > this list.  On Solaris and Tru64, at least, a threaded app shows up as
> > one entry in top.
> >
> > --
> > Dan Nelson
> > dnelson@stripped
> >
> > ---------------------------------------------------------------------
> > Before posting, please check:
> >    http://www.mysql.com/manual.php   (the manual)
> >    http://lists.mysql.com/           (the list archive)
> >
> > To request this thread, e-mail <mysql-thread113753@stripped>
> > To unsubscribe, e-mail <mysql-unsubscribe-dave=cc0.net@stripped>
> > Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
> >
> >
>
>
> ---------------------------------------------------------------------
> Before posting, please check:
>    http://www.mysql.com/manual.php   (the manual)
>    http://lists.mysql.com/           (the list archive)
>
> To request this thread, e-mail <mysql-thread113754@stripped>
> To unsubscribe, e-mail
<mysql-unsubscribe-joc=presence-pc.com@stripped>
> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
>
>
>
>

Thread
Growing memory usage/processesDave4 Jul
  • Re: Growing memory usage/processesDan Nelson4 Jul
  • Re: Growing memory usage/processesDave4 Jul
  • Re: Growing memory usage/processesJocelyn Fournier4 Jul