Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 21 Mar 2001 14:30:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 21 Mar 2001 14:30:09 -0500 Received: from adsl-63-195-162-81.dsl.snfc21.pacbell.net ([63.195.162.81]:25868 "EHLO master.linux-ide.org") by vger.kernel.org with ESMTP id ; Wed, 21 Mar 2001 14:29:55 -0500 Date: Wed, 21 Mar 2001 11:29:00 -0800 (PST) From: Andre Hedrick To: linux-kernel@vger.kernel.org Subject: Re: UDMA 100 / PIIX4 question In-Reply-To: <20010321095533Z131410-407+1932@vger.kernel.org> Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hello Geoff, Thanks Mark for doing a great job while I was doing other stuff. On Wed, 21 Mar 2001 quintaq@yahoo.co.uk wrote: > The result of hdparm -tT /dev/hda was, however, exactly the same as > before (ie circa 15 MB/sec. The results for /dev/hda7 remain at about > 30 MB/sec. You may get a burst because of caching prefetch or predictive readahead, but that is artifical; however, in your case the root directory begins 25% in the drive. /sbin/hdparm -t /dev/hda2 /dev/hda5 /dev/hda6 /dev/hda7 /dev/hda8 /dev/hda9 /dev/hda10 /dev/hda2: Timing buffered disk reads: 64 MB in 1.80 seconds = 35.56 MB/sec /dev/hda5: Timing buffered disk reads: 64 MB in 1.85 seconds = 34.59 MB/sec /dev/hda6: Timing buffered disk reads: 64 MB in 1.90 seconds = 33.68 MB/sec /dev/hda7: Timing buffered disk reads: 64 MB in 1.95 seconds = 32.82 MB/sec /dev/hda8: Timing buffered disk reads: 64 MB in 1.95 seconds = 32.82 MB/sec /dev/hda9: Timing buffered disk reads: 64 MB in 2.13 seconds = 30.05 MB/sec /dev/hda10: Timing buffered disk reads: 64 MB in 2.13 seconds = 30.05 MB/sec Disk /dev/hda: 255 heads, 63 sectors, 3737 cylinders Units = cylinders of 16065 * 512 bytes Device Boot Start End Blocks Id System /dev/hda1 * 1 7 56196 83 Linux /dev/hda2 8 269 2104515 83 Linux /dev/hda3 270 3737 27856710 5 Extended /dev/hda5 270 661 3148708+ 83 Linux /dev/hda6 662 923 2104483+ 83 Linux /dev/hda7 924 1119 1574338+ 83 Linux /dev/hda8 1120 1642 4200966 83 Linux /dev/hda9 1643 1773 1052226 83 Linux /dev/hda10 1774 3737 15775798+ 83 Linux > Further, even though the relevant line was commented out of fstab, I > could still perform hdparm -tT /dev/hda1 (giving the usual 15 MB/sec). > I suppose that this is because fdisk still showed : > > Disk /dev/hda: 255 heads, 63 sectors, 3737 cylinders > Units = cylinders of 16065 * 512 bytes > > Device Boot Start End Blocks Id System > /dev/hda1 * 1 932 7486258+ b Win95 FAT32 > /dev/hda2 933 3737 22531162+ 5 Extended > /dev/hda5 933 935 24066 83 Linux > /dev/hda6 936 952 136521 82 Linux swap > /dev/hda7 953 3737 22370481 83 Linux First you have the faster portion of the drive using a lame OS, so do not expect Linux to perform if you put it on the slowest portions of the device. > On the other hand, am I correct in interpreting the bonnie output for > the block read (included in my earlier post), of 20937 KB/sec as > reasonably healthy for my DTLA (ie consistent with hdparm's 30 MB/sec), > when performing more realistic tasks on the linux filesystem ? Yes if you adjust for ZONES. [root@via DiskPerf-1.0.3]# ./DiskPerf /dev/hda Device: IBM-DTLA-307030 Serial Number: YKDYKM37674 LBA 0 DMA Read Test = 56.53 MB/Sec (4.42 Seconds) Outer Diameter Sequential DMA Read Test = 35.47 MB/Sec (7.05 Seconds) Inner Diameter Sequential DMA Read Test = 17.74 MB/Sec (14.09 Seconds) As you can clearly see a single sector v/s outer v/s inner zones produce different transfer throughputs. > Regards, > > Geoff Andre Hedrick Linux ATA Development - 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/