[PERFORM] Performance problems on 4/8way Opteron (dualcore) HP DL585

[Dirk Lutzebäck]

Hi,

does anybody have expierence with this machine (4x 875 dual core Opteron 
CPUs)? We run RHEL 3.0, 32bit and under high load it is a drag. We 
mostly run memory demanding queries. Context switches are pretty much 
around 20.000 on the average, no cs spikes when we run many processes in 
parallel. Actually we only see two processes in running state! When 
there are only a few processes running context switches go much higher. 
At the moment we are much slower that with a 4way XEON box (DL580).


We are running 8.0.3 compiled with -mathlon flags.

Regards,

Dirk

---(end of broadcast)---
TIP 2: Don't 'kill -9' the postmaster

Re: [PERFORM] Performance problems on 4/8way Opteron (dualcore) HP DL585

[Josh Berkus]

Dirk,

 does anybody have expierence with this machine (4x 875 dual core Opteron
 CPUs)?

Nope.   I suspect that you may be the first person to report in on 
dual-cores.  There may be special compile issues with dual-cores that 
we've not yet encountered.

 We run RHEL 3.0, 32bit and under high load it is a drag. We 
 mostly run memory demanding queries. Context switches are pretty much
 around 20.000 on the average, no cs spikes when we run many processes in
 parallel. Actually we only see two processes in running state! When
 there are only a few processes running context switches go much higher.
 At the moment we are much slower that with a 4way XEON box (DL580).

Um, that was a bit incoherent.  Are you seeing a CS storm or aren't you?

-- 
--Josh

Josh Berkus
Aglio Database Solutions
San Francisco

---(end of broadcast)---
TIP 9: In versions below 8.0, the planner will ignore your desire to
   choose an index scan if your joining column's datatypes do not
   match