Bill Moran wrote:
On Tue, 06 Jun 2006 09:19:10 -0400
Jacob Coby <jcoby@xxxxxxxxxxxxxxx> wrote:
We recently upgraded from php 4.3.10 to 5.1.2, and the %system time has
skyrocketed:
Cpu(s): 42.8% us, 43.6% sy, 0.0% ni, 11.3% id, 2.2% wa, 0.2% hi, 0.0% si
Mem: 8312844k total, 7566168k used, 746676k free, 22356k buffers
Swap: 2040244k total, 520k used, 2039724k free, 6920384k cached
it used to be around 5% to 10%. The server is a quad-xeon dell pe 6650
running CentOS 4.2 with 8G of RAM running pg 8.1.1.
How can I determine what is causing such high system load? it seems to
have immediately jumped with the php upgrade.
This sounds more like a PHP question than a PostgreSQL question.
I know. I'm looking for advice on what would affect system time. Its
actually not related so much to the php upgrade as a major code change
we did. What baffles me is that the db abstraction layer didn't change.
However, we had a similar problem recently, and I ran ktrace (on FreeBSD)
to track down the system calls. 2 things jumped out:
1) pg_connect() creates a LOT of system time compared to pg_pconnect()
We use pg_pconnect(). We also reuse connections to avoid the overhead
of RESET ALL (php issues a RESET ALL on persistent connections, which
can take up to 0.1s)
2) require_once() and include_once() are truly evil.
Can you elaborate a bit on this? Privately if you want since it's off
topic for this list.
Thanks.
--
Jacob Coby
