Re: postgresql hanging (blocking) with smp kernel

> Marcel Groner wrote:
>
>> I have a problem with postgresql runnung on smp kernel.
>>
>> setup:
>>
>> master:
>> -------
>> - Pentium 4 (hyperthreading)
>> - 2 GB Memory
>> - os: fedora core 1
>> - kernel: 2.4.22-1.2188.nptlsmp
>> - postgresql: 7.4.3-1PGDG
>>
>> slave 1:
>> --------
>> - Pentium 4 (hyperthreading)
>> - 2 GB Memory
>> - os: fedora core 1
>> - kernel: 2.4.22-1.2115.nptlsmp
>> - postgresql: 7.4.3-1PGDG
>>
>> slave 2:
>> --------
>> - Double Xeon (with hyperthreading)
>> - 2 GB Memory
>> - os: fedora core 1
>> - kernel: 2.4.22-1.2199.nptlsmp
>> - postgresql: 7.4.3-1PGDG
>>
>>
>> the "replication" is made by hand. reading from slave 1 or slave 2
>> (balanced) and wrtiting to master, slave 1 and slave 2. Our site is a
>> high-traffic site (the biggest dating-site in switzerland:
>> www.swissflirt.ch) with > 1400 concurrent users and > 40'000 visits
>> per day.
>>
>> master and slave 1 (with pentium 4) are working perfectly with
>> smp-kernel. slave 2 (with double xeon) has big problems. running p.e.
>> with kernel 2.4.22 (non smp) works also but of course only one CPU is
>> used. when I use the smp kernel, the connections (and queries) are
>> hanging (blocking) after some short time. Also when I shutdown the
>> application (using java and jdbc to connect to the databases) the
>> postgres-processes (on slave 2) keep existing while the processes on
>> master and slave 1 shutdown propertly.
>
> Hanging on what ? I'm running postgres in a similar server ( the HT is
> enabled too so is like 4 CPU) without any problem at all.
>
> Show as "select * from pg_stat_activity"
> "select * from pg_locks"
>
>
> Regards
> Gaetano Mendola

Hi Gaetano

OK, here is the output from the two queries attached as textfile.
Theres another issue: I'm running the database completely in the memory. I
created a new location on the shared-memory-device (/dev/shm) with
initlocation and created the database there. Could that also be a problem?
on slave 1 (HT Pentium 4) it works and there the location of the database
is also /dev/shm.

Regards
Marcel Groner