Re: log buffer size and log file syncs
From: Tanel Poder <tanel_at_tanelpoder.com>
Date: Tue, 1 May 2012 01:20:41 +0300
Message-ID: <CAMHX9JLcjkhLdGL45bpWR=cGmD7WEZAY31+T13X7w7Y2iu5_CA_at_mail.gmail.com>
Which OS are you on? If it happens to be Solaris, then prstat -mLp *PID*would show the scheduling latency for LGWR. This would help to find out
whether LGWR is CPU starved or not.... what load averages do you have? Also, what does snapper say when ran on LGWR? If you have synchronous DG for example, then LGWR would wait for the LNS ack too in addition to the log file parallel write wait, before returning OK back to the committing session ...
Date: Tue, 1 May 2012 01:20:41 +0300
Message-ID: <CAMHX9JLcjkhLdGL45bpWR=cGmD7WEZAY31+T13X7w7Y2iu5_CA_at_mail.gmail.com>
Which OS are you on? If it happens to be Solaris, then prstat -mLp *PID*would show the scheduling latency for LGWR. This would help to find out
whether LGWR is CPU starved or not.... what load averages do you have? Also, what does snapper say when ran on LGWR? If you have synchronous DG for example, then LGWR would wait for the LNS ack too in addition to the log file parallel write wait, before returning OK back to the committing session ...
Tanel.
On Mon, Apr 30, 2012 at 5:56 PM, CRISLER, JON A <JC1706_at_att.com> wrote:
> Interesting thoughts Tanel: in this case of this specific app, the
> majority of the work is made of up small commits to a handful of tables on
> a 6 node RAC cluster. I/O times are generally quite good, and with 32
> cores per node the CPU and load average is very low. Its 11gR1 – I was
> wondering if some of the tweaks to put LGWR at “real time” priority that
> are mentioned for 10g also apply to 11g.****
>
>
>
-- http://www.freelists.org/webpage/oracle-lReceived on Mon Apr 30 2012 - 17:20:41 CDT