Comments on: Request for Testing – SYSEMU Performance Patches

By: vitrum

vitrum — Mon, 14 Jun 2004 21:17:24 +0000

interesting… is this similar to the skas patch?

By: bakins

bakins — Mon, 14 Jun 2004 06:09:31 +0000

I was out of town for a week.

I’ve now migrated and am testing. Everything seems to work. I’m testing out plone. I’ll do some tests and get back.

By: caker

caker — Sat, 05 Jun 2004 03:45:16 +0000

[quote:f84ba42be4="bakins"]where is the migrate button? I shutodown and clicked around but I never found it.[/quote]
This is something I have to set up for you first (which I just did). Login and you should see it.

Testing has gone very well. In fact, the machine is “live”, 2.6.7-rc1 is performing great (on the host), and the linode29 kernel works perfectly on SYSEMU and non-SYSEMU patched hosts.

I consider this test done, but go ahead and make the move — let me know what you think.

-Chris

By: bakins

bakins — Fri, 04 Jun 2004 23:29:03 +0000

where is the migrate button? I shutodown and clicked around but I never found it.

By: terryr

terryr — Mon, 31 May 2004 13:41:11 +0000

[quote:befbb85d95="caker"]I’ll give this a shot, too, but.. would you mind rebooting into the linode28 kernel and seeing if you can reproduce this? [/quote]

Did that yesterday with no change, but when I checked this morning, I’m at 0.1% for irq and softirq and it cycles with iowait at 0.2%. The high initial numbers didn’t seem to affect performance at all.

–
Terry

By: jftuga

jftuga — Mon, 31 May 2004 13:24:29 +0000

I have modified the mysql server for a small memory footprint using the my-small.cnf that comes with the src distro.

I will let you kno if this helps.

Also, I am using a lot of swap, and am considering upgrading to a 96 or 128 when they become available.

-John

By: caker

caker — Mon, 31 May 2004 13:18:42 +0000

[quote:2ab259ee1d="terryr"]I don’t recall this happening when I looked at top on the old host. Or did I just miss it? [/quote]
I’ll give this a shot, too, but.. would you mind rebooting into the linode28 kernel and seeing if you can reproduce this?

I somehow doubt the SYSEMU patch would be the cause of this, or the mysql problem…

-Chris

By: caker

caker — Mon, 31 May 2004 13:13:08 +0000

[quote:04e5122a27="jftuga"]I am seeing stragne problems with mysql that I did not see before moving over. Whenever, I try to connect I get this message:

ERROR 2002: Can’t connect to local MySQL server through socket ‘/var/run/mysqld/mysqld.sock’ (2)

This is because mysqld either keeps hanging or completely crashes.
It will run fine for a few hours and then just die. I can’t explain why.[/quote]
I’ve noticed your Linode using a lot of swap, so perhaps you’re running out of memory and the OOM (Out Of Memory) killer is kicking in…

-Chris

By: jftuga

jftuga — Mon, 31 May 2004 12:58:57 +0000

I am seeing stragne problems with mysql that I did not see before moving over. Whenever, I try to connect I get this message:

ERROR 2002: Can’t connect to local MySQL server through socket ‘/var/run/mysqld/mysqld.sock’ (2)

This is because mysqld either keeps hanging or completely crashes.
It will run fine for a few hours and then just die. I can’t explain why.

I will keep everyone posted.

John

By: terryr

terryr — Sat, 29 May 2004 10:53:14 +0000

I loaded a fresh Fedora Core 1 distro. Noticed immediately how much faster it is. Ran locate -u which was noticeably faster. Ran top and saw something strange. About every two seconds, there’s a cycle. See pics below. irq goes up to 0.9% and softirq goes up to 49.5% and iowait is 49.5%, then it all drops to 0 for 2 seconds and goes back up again for two seconds.

[img]http://futurecourse.com/files/no_softirq.gif[/img]
[img]http://futurecourse.com/files/softirq.gif[/img]

I don’t recall this happening when I looked at top on the old host. Or did I just miss it?

Terry