I will look at it. In the meanwhile I did find at least one of the standby processes reading in bursts every 60-70 seconds like 400MB in 14.xx seconds from control01.ctl, even that file is only 94MB large.
> -----Original Message----- > From: Andrew Phillips [mailto:[EMAIL PROTECTED] > Sent: Tuesday, February 19, 2008 01:43 > To: Ulf Zimmermann > Cc: [email protected] > Subject: RE: [Ocfs2-users] Anyone have an idea how to find file > i/othroughput? > > Ulf, > > Have you considered using systemtap? There is a recipe here that could > be used to find out whats going on; > > http://sourceware.org/systemtap/wiki/WSDeviceMonitor?highlight=%28% > 28WarStories%29%29 > > I'm not sure how well that would work with ocfs2. Unlike dtrace, > systemtap can be more "uneven" in coverage. Its also something that > requires a bit of fiddling (installing debuginfo packages). > > The recipe above traps vfs_read and vfs_write so should work as a > first stab at identifying the process id thats causing the I/O. > > I'd also advise some thought if its to be used on a production > environment. Having said that, I've used it on a production oracle RAC > database server and found it very valuable. > > I don't recall you mentioning the distribution, but RH, CentOS, and > oracle's version of CentOS should all work. > > As always, read the instructions on the label, etc... > > Andy > > > On Mon, 2008-02-18 at 23:14 -0800, Ulf Zimmermann wrote: > > Forgot to mention, this remote server is just Oracle. It has one standby > > database and one local database, the local one is suppose to be idle, > > i.e. nothing connecting to it, besides once in a while for available > > check. > > > > While the primary database of the standby was down, I saw less disk read > > access, but every 5 minutes for about 60 seconds I would see > > 50-60MB/sec. After the primary came back up, read access is as high as > > 160MB/sec. > > > > We are only seeing it on this single node of the remote standby. The > > local standby (on EXT3) is not doing the same thing. > > > > > -----Original Message----- > > > From: Sunil Mushran [mailto:[EMAIL PROTECTED] > > > Sent: Monday, February 18, 2008 19:28 > > > To: Ulf Zimmermann > > > Cc: [email protected] > > > Subject: Re: [Ocfs2-users] Anyone have an idea how to find file i/o > > > throughput? > > > > > > If a userspace process is behind the io surge, then strace should > > help. > > > But determining the process may require a bit of trial and error. > > > > > > Ulf Zimmermann wrote: > > > > We got a remote Oracle 10g R2 standby running on OCFS2. Initial when > > we > > > > started the standby, read I/O was < 5MB/sec on average. Since then > > it > > > > has grown to over 40MB/sec (longer average, it peaks much higher). > > Here > > > > is a graph showing this: > > > > > > > > http://www.alameda.net/~ulf/dbphx01.png > > > > > > > > We also have a local standby running (on EXT3) which is not showing > > the > > > > same symptom. I am trying to find where all these reads are > > happening. > > > > Anyone have an idea how to figure that out on Linux? > > > > > > > > Ulf. > > > > > > > > > > > > _______________________________________________ > > > > Ocfs2-users mailing list > > > > [email protected] > > > > http://oss.oracle.com/mailman/listinfo/ocfs2-users > > > > > > > > > > _______________________________________________ > > Ocfs2-users mailing list > > [email protected] > > http://oss.oracle.com/mailman/listinfo/ocfs2-users > > ________________________________________________________________________ > In order to protect our email recipients, Betfair Group use SkyScan from > MessageLabs to scan all Incoming and Outgoing mail for viruses. > > ________________________________________________________________________ _______________________________________________ Ocfs2-users mailing list [email protected] http://oss.oracle.com/mailman/listinfo/ocfs2-users
