RES: Context switching

["Carlos H. Reimer" <carlos(dot)reimer(at)opendb(dot)com(dot)br>]

Hi,

 

Sorry, but this message was already post some days before!

 

Thank you!

 

Carlos

 

-----Mensagem original-----
De: pgsql-performance-owner(at)postgresql(dot)org [mailto:pgsql-performance-owner(at)postgresql(dot)org]Em nome de Carlos H. Reimer
Enviada em: quarta-feira, 1 de novembro de 2006 03:23
Para: pgsql-performance(at)postgresql(dot)org
Assunto: [PERFORM] Context switching

Hi,

 

We've migrated one of our servers from pg 7.4 to 8.1 and from times to times (4 hours) the server start doing a lot of context switching and all transactions become very slow.

 

The average context switching for this server as vmstat shows is 1 but when the problem occurs it goes to 250000.

 

CPU and memory usage are ok.

 

What can produce this context switching storms?

 

It is a box with 12GB RAM and 4 processors running RedHat Enterprise Linux AS.

 

Thank you in advance!

Reimer
carlos(dot)reimer(at)opendb(dot)com(dot)br
OpenDB Serviços e Treinamentos PostgreSQL e DB2
Fone: 47 3327-0878 Cel: 47 9602-0151
www.opendb.com.br