* Otto Moerbeek <[EMAIL PROTECTED]> [2006-06-08 10:00]:
> On Thu, 8 Jun 2006, Michael Erdely wrote:
>
> > Hi,
> >
> > I've got a Dell Dimension XPS B866r desktop running as my web/mail server
> > (recently upgraded to 3.9).
> >
> > Occasionally, after a seemingly random amount of time, the machine will do
> > one
> > of two things: it will either lockup/freeze where there are no messages on
> > the
> > console, but you cannot type, ping or access the box in any way (but the
> > reset
> > button) OR, since I have ddb.panic=0, it will reboot with the following
> > message from my serial console:
> > panic: semop - can't undo undos
> > Starting stack trace...panic(fffffff4,3,e870df10,2,fffffff4) at
> > panic+0x71panic(d051c1f6,e870dec8,12,d6a4f2d0,3) at panic+0x71
> > sys_semop(d658b2f0,e870df68,e870df58,0,1998c) at sys_semop+0x492syscall() at
> > syscall+0x2ea
> > --- syscall (number 290) ---0x444e4e9:
> > End of stack trace.
> > syncing disks... 19 19 donerebooting...
> >
> > Since the box rebooted automatically, I don't have ps output, but the box is
> > running: stock GENERIC kernel, mysql-server-5.0.22, stock apache (chrooted)
> > w/
> > ssl, courier-imap/pop3 w/ssl, imap-proxy,
> > php5-core,curl,gd,imap,mbstring,mcrypt,mysql-5.1.4-hardened (compiled from
> > CVS
> > ports of -current), wordpress-2.0.3, gallery-2.1.1, squirrelmail 1.4.6 and
> > 1.5.1, spamd (openbsd), spamassassin (spamc+spamd+procmail), clamav
> > (clamav-milter + clamd), sendmail (with sasl compiled in), sasl with
> > mysql+crypt patch applied, pure-ftpd (requiring ssl... not really used).
> >
> > When the box comes back up, none of the log files have error messages.
> >
> > Let me know if I can provide any more info.
> > Does anyone have any thoughts? I'm thinking that I'm running too much on my
>
> your system is running out of semaphore undo data structures. Try
> increasing at least kern.seminfo.semmnu. Other semaphore related
> sysctl's might need an increase as well.
>
And mysqueal sucks...
Your system may run out of other things as well given the bloatware
you're running on it. anything else I have mysqeal on and any
significant amount of users I usually have to crank up quite a few of
the default limits, both in the kernel and in mysql - I usually build
a GENERIC with maxusers=128 to start, and then find the 80 bazillion
knobs in mysqeal to turn to tell it to use file descriptors. no really
use more than 100 file descriptors. no really really use more than
100 file descriptors....
If you have a small number of users you may be fine. however
seeing what you have there and 512 mb of ram, you may want a bit more
if you have significant(1) usage.
Did I mention that mysqueal sucks?
-Bob
1) Your notion of "significant" may not be mine - Our "similar" boxes
cluster a load of up to 2500 simultaneous sessions with up to 300
"click the thingy at the same time"... They've all got 2 gig of ram
and there are 7 (I think atm) of them.
