The problem is not apparent from the driver messages. There are no error messages from the driver per se. What driver version was used in CentOS 4? Regards, Sumant -----Original Message----- From: linux-scsi-owner@xxxxxxxxxxxxxxx [mailto:linux-scsi-owner@xxxxxxxxxxxxxxx] On Behalf Of James Bottomley Sent: Sunday, October 28, 2007 7:27 AM To: Anthony Ewell Cc: linux-scsi Subject: Re: slow after upgrade to CentOS 5 (RHEL5) On Sat, 2007-10-27 at 13:21 -0700, Anthony Ewell wrote: > James Bottomley wrote: > > On Wed, 2007-10-24 at 18:04 -0700, Anthony Ewell wrote: > >> Hi All, > >> > >> If you all would not mind a post from the general public Linux > >> user, after doing a complete disk wipe of CentOS 4 and installing > >> CentOS5, my system is preceived to be 3 times slower. > >> > >> To troubleshooting this, I made a post on CentOS's > >> bugzilla: http://bugs.centos.org/view.php?id=2382 > >> > >> Would some of the experts on this group mind looking at the > >> bug to evaluate the possibility that it is being caused by the > >> underlying scsi > >> driver? The post contains a dmesg from "Computer C". > >> (Yes, I am getting a bit desperate.) > > > > There's still too little information in the bug report to tell much > > of anything. The dmesg doesn't indicate any anomaly with the > > megaraid (although the LSI people might be able to tell better). > > However, it also doesn't contain a trace of the tape drive. > > > > Best guess would be a slow down in the megaraid driver. Can you try > > doing a speed test on it? (hdparm -t should suffice). > > > > James > > > Hi James, > > The other guy reporting the problem > > http://www.centos.org/modules/newbb/viewtopic.php?topic_id=10659&start > =0#forumpost34209 is not using a MegaRAID card. He is using 3ware9508 > Raid Controllers. > He is also using a different processor (amd vs xeon) and a different > chipset (Intel Greenwood vs nVidia) > > I also spoke to Neela Kolli (Mega RAID maintainer) and he said he'd > never heard of the problem. Here are some tests (including dhparm) > that I sent to Neela (he never wrote back). > > I have also checked with Stellen over at the "dump" > list and he has not seen the problem (yet). > > The problem occurs when backing up to a two different types of tape > drives and to an eSata drive. > > When I am running a "dump" on computer C, gnome-system-monitor shows > my two cores running at only about 10 to 20% and switching back and > forth (one at 0% the other at 20% for about 5 seconds, then switching > positions) > > On Computer C (Cent OS 5), when typing in Word Pro (a windows word > processor) in Parallels, I can watch myself type. Computer B (CentOS > 4.4, now 4.5) has the same version of Parallels installed on it > (Parallels-2.2.2112-lin.i386) that computer C (CentOS 5) has. The > perceived speed difference is about a factor of three (you can not > watch yourself type). > > All the "Low Level" test I run seem to come out the same between Cent > OS 4.4 and 5. Very frustrating! It is almost like some system > monitor component is looking at everything and slowing things down. > If this was Windows, I'd go straight to the Anti Virus as the culprit. > (Does SE Linux do such > things?) > > Are there any performance tests I can run for you? > > Thank you for letting me ramble, this problem is really frustrating. > I am afraid to any additional CentOS5 server out there and CentOS 4.x > is so terribly out of date. > > -T > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > Tests I sent to Neela: > > CentOS 5 (2.6.18-8.1.8.el5, Sata150-4): > > #grep -i bogomips /var/log/dmesg > Calibrating delay using timer specific routine.. 4001.91 BogoMIPS > (lpj=2000959) > Calibrating delay using timer specific routine.. 3999.58 BogoMIPS > (lpj=1999791) > Total of 2 processors activated (8001.50 BogoMIPS). > > > #/sbin/hdparm -t /dev/sda > /dev/sda: > Timing buffered disk reads: 236 MB in 3.01 seconds = 78.53 MB/sec > > > #/sbin/hdparm -t /dev/sdb > /dev/sdb: > Timing buffered disk reads: 182 MB in 3.01 seconds = 60.37 MB/sec > > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > CentOS 4.4 (linux rescue 2.6.9-42.EL, IDE): > > #cat /proc/cpuinfo > bogomips : 4002.92 > > #/sbin/hdparm -t /dev/sda > /dev/sda: > Timing buffered disk reads: 216 MB in 3.01 seconds = 71.87 MB/sec > > #/sbin/hdparm -t /dev/sdb > /dev/sdb: > Timing buffered disk reads: 184 MB in 3.01 seconds = 61.18 MB/sec That pretty much shows, if anything, that transfer speed improved from .9 to .18. > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > CentOS 5 (2.6.18-8.1.3.el5, Sata300-4): > #grep -i bogomips /var/log/dmesg > Calibrating delay using timer specific routine.. 4001.92 BogoMIPS > (lpj=2000960) > Calibrating delay using timer specific routine.. 3999.58 BogoMIPS > (lpj=1999794) > Total of 2 processors activated (8001.50 BogoMIPS). > > #/sbin/hdparm -t /dev/sda > /dev/sda: > Timing buffered disk reads: 214 MB in 3.02 seconds = 70.86 MB/sec > > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > CentOS 5 (2.6.18-10.1.3.el5, Sata300-4): > > eSata: dump -0a -z -f /dev/nul winxp.hdd > DUMP: Volume 1 took 0:04:04 > DUMP: Volume 1 transfer rate: 4247 kB/s > DUMP: Volume 1 1567020kB uncompressed, 1036385kB compressed, > 1.513:1 > > eSata: dump -0a -f /dev/nul winxp.hdd (no compression) > DUMP: Volume 1 1036420 blocks (1012.13MB) > DUMP: Volume 1 took 0:02:09 > DUMP: Volume 1 transfer rate: 8034 kB/s > > > 150-4: dump -0a -z -f /dev/nul winxp.hdd > DUMP: Volume 1 took 0:04:05 > DUMP: Volume 1 transfer rate: 4230 kB/s > DUMP: Volume 1 1573150kB uncompressed, 1036383kB compressed, > 1.518:1 > > 150-4: dump -0a -f /dev/nul winxp.hdd (no compression) > DUMP: Volume 1 1036420 blocks (1012.13MB) > DUMP: Volume 1 took 0:02:05 > DUMP: Volume 1 transfer rate: 8291 kB/s I think this is beginning to point to problems with dump. What are the corresponding figures for dump under 2.6.9 (or are the two sets of figures centos5 followed by centos4)? James - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
