------------------------------------------------------ Martin Knoblauch email: k n o b i AT knobisoft DOT de www: http://www.knobisoft.de
----- Original Message ---- > From: Alasdair G Kergon <[EMAIL PROTECTED]> > To: Martin Knoblauch <[EMAIL PROTECTED]> > Cc: Linus Torvalds <[EMAIL PROTECTED]>; Mel Gorman <[EMAIL PROTECTED]>; > Fengguang Wu <[EMAIL PROTECTED]>; Mike Snitzer <[EMAIL PROTECTED]>; Peter > Zijlstra <[EMAIL PROTECTED]>; [EMAIL PROTECTED]; Ingo Molnar <[EMAIL > PROTECTED]>; linux-kernel@vger.kernel.org; "[EMAIL PROTECTED]" <[EMAIL > PROTECTED]>; [EMAIL PROTECTED]; Jens Axboe <[EMAIL PROTECTED]>; Milan Broz > <[EMAIL PROTECTED]>; Neil Brown <[EMAIL PROTECTED]> > Sent: Tuesday, January 22, 2008 3:39:33 PM > Subject: Re: regression: 100% io-wait with 2.6.24-rcX > > On Fri, Jan 18, 2008 at 11:01:11AM -0800, Martin Knoblauch wrote: > > At least, rc1-rc5 have shown that the CCISS system can do well. Now > > the question is which part of the system does not cope well with the > > larger IO sizes? Is it the CCISS controller, LVM or both. I am > open > to > > suggestions on how to debug that. > > What is your LVM device configuration? > E.g. 'dmsetup table' and 'dmsetup info -c' output. > Some configurations lead to large IOs getting split up on the > way > through > device-mapper. > Hi Alastair, here is the output, the filesystem in question is on LogVol02: [EMAIL PROTECTED] ~]# dmsetup table VolGroup00-LogVol02: 0 350945280 linear 104:2 67109248 VolGroup00-LogVol01: 0 8388608 linear 104:2 418054528 VolGroup00-LogVol00: 0 67108864 linear 104:2 384 [EMAIL PROTECTED] ~]# dmsetup info -c Name Maj Min Stat Open Targ Event UUID VolGroup00-LogVol02 253 1 L--w 1 1 0 LVM-IV4PeE8cdxA3piC1qk79GY9PE9OC4OgmOZ4OzOgGQIdF3qDx6fJmlZukXXLIy39R VolGroup00-LogVol01 253 2 L--w 1 1 0 LVM-IV4PeE8cdxA3piC1qk79GY9PE9OC4Ogmfn2CcAd2Fh7i48twe8PZc2XK5bSOe1Fq VolGroup00-LogVol00 253 0 L--w 1 1 0 LVM-IV4PeE8cdxA3piC1qk79GY9PE9OC4OgmfYjxQKFP3zw2fGsezJN7ypSrfmP7oSvE > See if these patches make any difference: > http://www.kernel.org/pub/linux/kernel/people/agk/patches/2.6/editing/ > > dm-md-merge_bvec_fn-with-separate-bdev-and-sector.patch > dm-introduce-merge_bvec_fn.patch > dm-linear-add-merge.patch > dm-table-remove-merge_bvec-sector-restriction.patch > thanks for the suggestion. Are they supposed to apply to mainline? Cheers Martin -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
