On Mon, 7 May 2001, Rene Tegel wrote:
> On Mon, 7 May 2001 07:40:26 -0400 (EDT)
> <[EMAIL PROTECTED]> wrote:
>
> >
> > Thanks for the quick reply.
> >
> > I set max_connections so low because even at peaks I never need more, and
> > when the slowdowns happen, it seems to have an easier time recovering if
> > there are 15 slow connections hanging than if there are hundreds.
>
> Are you saying you have 15 slow queries and thus only 3 connections available for
>your site to run at time server crashes? that's wrong and probably one of the reasons
>your site slows down.
>
> I guess you have some script(s) with 'corrupt' queries that take loads of time (on
>non-indexed fields or something) to complete. So mysql gets more and more slow
>queries which may take hours to complete, whilst slowing down your site.
> You should check which script(s) are responsible for this, and fix the bugs.
>
I'm not really talking about the web site slowing down here (of course it
does), I'm talking about the queries themselves slowing down.
I do have some queries which could use optimization, but they're in no way
"corrupt". All queries are run regularily during the 24 hour period during
which the server runs fine. Then suddenly the same queries start taking
several seconds, sometimes even minutes. This leads to the processes
building up and waiting for locks, but at that point the server is already
screwed; the 18 processes are busy and if I had max_connections at 200,
then 200 processes would be busy after not too long.
This system is getting an average of 4 page requests every second, it's
fairly obvious that the battle is lost once queries start taking more than
a few seconds.
> >
> > I'll try the thread concurrency thing, thanks. I was under the impression
> > this variable was only effective on a Solaris box, but I may be wrong?
>
> you might be quite right. i just noticed it was not the default..
>
> >
> > I suspect you may be right about linuxthreads being the problem.
> > Unfortunately, I'm on a managed hosting solution, and I'm not sure if I
> > want to risk a kernel panic and countless hours of expensive support :)
>
> you always could try if same database/scripts generate same errors on another box..
Too late, I already took the risk and upgraded to 2.4.4. Went smoothly :)
So now I'll just sit tight and see how it goes. Hopefully, the problems
are gone.
Thanks for the help,
Jon
---------------------------------------------------------------------
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 <[EMAIL PROTECTED]>
To unsubscribe, e-mail <[EMAIL PROTECTED]>
Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
