Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261980AbVBAKmw (ORCPT ); Tue, 1 Feb 2005 05:42:52 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261979AbVBAKmo (ORCPT ); Tue, 1 Feb 2005 05:42:44 -0500 Received: from ns.virtualhost.dk ([195.184.98.160]:64909 "EHLO virtualhost.dk") by vger.kernel.org with ESMTP id S261973AbVBAKmT (ORCPT ); Tue, 1 Feb 2005 05:42:19 -0500 Date: Tue, 1 Feb 2005 11:42:14 +0100 From: Jens Axboe To: "Catalin(ux aka Dino) BOIE" Cc: linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org Subject: Re: Strange vmstat output. 2.6.10 Scheduler? Message-ID: <20050201104214.GK4137@suse.de> References: <20050201102638.GJ4137@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5225 Lines: 154 On Tue, Feb 01 2005, Catalin(ux aka Dino) BOIE wrote: > > >On Tue, Feb 01 2005, Catalin(ux aka Dino) BOIE wrote: > >>Hello! > >> > >>I have a weird problem with a server. I use deadline. > >>The output of vmstat is: > >> 1 1 12312 6064 7580 815432 0 0 5332 456 1263 3119 22 5 > >> 0 > >> 73 > >> 0 1 12312 5280 7584 816240 0 0 6204 620 1307 1530 15 4 > >> 0 > >> 81 > >> 0 1 12312 6096 7528 815088 0 0 7604 8732 1256 1398 5 8 > >> 0 > >> 87 > >> 0 1 12312 6048 7528 815144 0 0 8 8 1243 1440 14 2 > >> 0 > >> 84 > >> 0 1 12312 6048 7528 815168 0 0 0 0 1261 1287 8 2 > >> 0 > >> 90 > >> 0 2 12312 6040 7584 815184 0 0 0 0 1258 1197 7 2 > >> 0 > >> 91 > >> 0 2 12312 6024 7584 815208 0 0 0 0 1265 1309 6 5 > >> 0 > >> 89 > >> 0 2 12312 6024 7584 815208 0 0 0 136 1253 365 2 2 > >> 0 > >> 96 > >> 0 2 12312 5984 7584 815208 0 0 0 0 1268 413 2 1 > >> 0 > >> 97 > >> 0 2 12312 6052 7584 815208 0 0 0 0 1270 375 2 1 > >> 0 > >> 97 > >> 1 0 12312 6164 7584 815156 0 0 6188 288 1270 4314 23 5 > >> 0 > >> 72 > >> 0 1 12312 5684 7536 815592 0 0 4128 8656 1270 1316 14 3 > >> 0 > >> 83 > >> 0 1 12312 5684 7536 815608 0 0 0 0 1258 1251 8 3 > >> 0 > >> 89 > >> 0 1 12312 5552 7536 815628 0 0 0 0 1258 1327 8 2 > >> 0 > >> 90 > >> 0 1 12312 5552 7536 815644 0 0 0 0 1264 1127 7 2 > >> 0 > >> 91 > >> 0 1 12312 5552 7536 815668 0 0 0 2 1258 1225 8 3 > >> 0 > >> 89 > >> 0 3 12312 5248 7588 816108 0 0 4340 585 1249 1316 7 3 > >> 0 > >> 90 > >> 0 2 12312 5612 7584 815680 0 0 3092 188 1254 411 3 1 > >> 0 > >> 96 > >> 0 2 12312 5564 7584 815676 0 0 0 0 1261 259 2 2 > >> 0 > >> 96 > >> 0 2 12312 5564 7584 815676 0 0 0 0 1254 348 2 1 > >> 0 > >> 97 > >> > >>It seems strange because iowait is at 90% but nothing is trasnfered > >>to/from disk. Why is that? > > > >The bi/bo numbers are sometimes a little confusing, it doesn't mean that > >the drive is actually doing 8656kb of io at that very second - only that > >this much io was queued to the drive. > > > >>I run postgresql on this server and I'm not satistied by it's speed. > >> > >>Single Pentium IV, IDE disk. > >> > >>What can be the problem? > > > >Do you have write cache enabled on the drive? > > No. Intentionaly I disabled it: > > ATA device, with non-removable media > Model Number: WDC WD800JB-00CRA1 > Serial Number: WD-WMA8E8797395 > Firmware Revision: 17.07W17 > Standards: > Supported: 5 4 3 2 > Likely used: 6 > Configuration: > Logical max current > cylinders 16383 16383 > heads 16 16 > sectors/track 63 63 > -- > CHS current addressable sectors: 16514064 > LBA user addressable sectors: 156301488 > device size with M = 1024*1024: 76319 MBytes > device size with M = 1000*1000: 80026 MBytes (80 GB) > Capabilities: > LBA, IORDY(can be disabled) > bytes avail on r/w long: 40 Queue depth: 1 > Standby timer values: spec'd by Standard, with device specific > minimum > R/W multiple sector transfer: Max = 16 Current = 16 > Recommended acoustic management value: 128, current value: 254 > DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 *udma5 > Cycle time: min=120ns recommended=120ns > PIO: pio0 pio1 pio2 pio3 pio4 > Cycle time: no flow control=120ns IORDY flow control=120ns > Commands/features: > Enabled Supported: > * READ BUFFER cmd > * WRITE BUFFER cmd > * Host Protected Area feature set > * Look-ahead > Write cache > * Power Management feature set > Security Mode feature set > * SMART feature set > * Device Configuration Overlay feature set > Automatic Acoustic Management feature set > SET MAX security extension > * DOWNLOAD MICROCODE cmd > * SMART self-test > * SMART error logging > Security: > supported > not enabled > not locked > frozen > not expired: security count > not supported: enhanced erase > HW reset results: > CBLID- above Vih > Device num = 0 determined by CSEL > Checksum: correct > > Thanks! Well then that is why, the writes are taking quite a while to reach the platter. Nothing is wrong, the drive is just slow :-) -- Jens Axboe - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/