FW: Latch Waits
I'm running 7.31.FD4 on Solaris 9.
Server had 32Gb memory 16 CPU
Regards
Colin
>From: "Colin Dawson" <cjd_1955@hotmail.com>
>Reply-To: colin@colindawson.com
>To: informix-list@iiug.org
>Subject: Latch Waits
>Date: Sun, 13 Mar 2005 09:34:29 +0000
>
>Hi,
>
>Yesterday I started getting a lot of latch waits - onstat -u had "S" in the
>1st position in the flags column. onstat -g lmx showed a lot of processes
>waiting on a mutex called "global cach" I cannot find much information
>about this mutex.
>
>The question I'm asking is why would I get this situation? It has been
>running fine previously. I did change BUFFERS from 1900000 to 4000000 and
>RESIDENT from -1 to 0. So why would changing these two parameters cause the
>mutex waits. When the change was made checkpoints went up from 1-3 seconds
>every 15 minutes to 5+ seconds every 5 minutes (leaving the interval at 15
>minutes meant we had checkpoints > 10 seconds)
>
>Some onconfig parameters:
>LRUS 511>CLEANERS 127 (onstat -u shows some page cleaners not doing any work - no of
>writes=0)
>CKPTINTVL 900
>LRU_MAX_DIRTY 1
>LRU_MIN_DIRTY 0
>RA_THRESHOLD 4
>NOAGE 1
>NETTYPE tlitcp,15,256,NET>
>onstat -u shows approx 1300 connections>
>Any insight into why I had the above problem would be appreciated.
>
>
>
>Many Thanks
>
>
>Colin Dawson
>
>www.ladbrokes.com
>
>
>sending to informix-list
sending to informix-list