From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Alan D. Brunelle" Date: Fri, 18 Jul 2008 15:28:30 +0000 Subject: Re: [Patch] blkiomon: repost with some fixes and improvements Message-Id: <4880B69E.3050806@hp.com> List-Id: References: <1216377086.8497.4.camel@kitka.ibm.com> In-Reply-To: <1216377086.8497.4.camel@kitka.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-btrace@vger.kernel.org > > Thanks for the patch, I'll give it a try today. > The most reliable way to reproduce is to run a dd that copies about > 10-20Gb, and rm the file immediately. > Then try that find / ^C stuff, it usually occurs right at the end of the > dd (when the file is probably removed). > > Best regards, > --Edwin The system /is/ acting very strange: I'm seeing very, very poor responsiveness - trying to start anything with very large dd's going on takes a long time (maybe forever, I'm just trying to log in right now and it won't budge). I do have vmstat & iostat running, what's strange is I'm seeing a lot of I/O from iostat: avg-cpu: %user %nice %system %iowait %steal %idle 0.47 0.00 2.14 90.51 0.00 6.88 Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sda 163.50 20.00 157296.00 40 314592 but /not/ vmstat (I thought I'd see the 'bo' column going): procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu---- r b swpd free inact active si so bi bo in cs us sy id wa 0 0 0 2795940 3326292 1649612 0 0 0 26 183 2104 8 0 92 0 Anyways, I'm hoping the Python script helps diagnose some stuff. I'm looking into how to measure other things that are put off because we are congested in the request allocation path... Alan