Messages in this thread | | | Date | Sun, 22 Aug 2004 11:33:49 +1000 | From | Nick Piggin <> | Subject | Re: Production comparison between 2.4.27 and 2.6.8.1 |
| |
Massimo Cetra wrote: > Hi everybody. > > #*********************************************************** > > Environment: > processor : 0 > vendor_id : AuthenticAMD > cpu family : 6 > model : 10 > model name : AMD Athlon(tm) XP 3000+ > stepping : 0 > cpu MHz : 2091.477 > > #*********************************************************** > total used free shared buffers > cached > Mem: 1030844 258500 772344 0 36924 > 167092 > -/+ buffers/cache: 54484 976360 > Swap: 2056304 0 2056304 > > #*********************************************************** > # lspci > 0000:00:00.0 Host bridge: nVidia Corporation nForce2 AGP (different > version?) (rev c1) > 0000:00:00.1 RAM memory: nVidia Corporation nForce2 Memory Controller 1 > (rev c1) > 0000:00:00.2 RAM memory: nVidia Corporation nForce2 Memory Controller 4 > (rev c1) > 0000:00:00.3 RAM memory: nVidia Corporation nForce2 Memory Controller 3 > (rev c1) > 0000:00:00.4 RAM memory: nVidia Corporation nForce2 Memory Controller 2 > (rev c1) > 0000:00:00.5 RAM memory: nVidia Corporation nForce2 Memory Controller 5 > (rev c1) > 0000:00:01.0 ISA bridge: nVidia Corporation nForce2 ISA Bridge (rev a4) > 0000:00:01.1 SMBus: nVidia Corporation nForce2 SMBus (MCP) (rev a2) > 0000:00:02.0 USB Controller: nVidia Corporation nForce2 USB Controller > (rev a4) > 0000:00:02.1 USB Controller: nVidia Corporation nForce2 USB Controller > (rev a4) > 0000:00:02.2 USB Controller: nVidia Corporation nForce2 USB Controller > (rev a4) > 0000:00:04.0 Ethernet controller: nVidia Corporation nForce2 Ethernet > Controller (rev a1) > 0000:00:08.0 PCI bridge: nVidia Corporation nForce2 External PCI Bridge > (rev a3) > 0000:00:09.0 IDE interface: nVidia Corporation nForce2 IDE (rev a2) > 0000:00:1e.0 PCI bridge: nVidia Corporation nForce2 AGP (rev c1) > 0000:01:04.0 Ethernet controller: Marvell Technology Group Ltd. Yukon > Gigabit Ethernet 10/100/1000Base-T Adapter (rev 13) > 0000:01:0b.0 RAID bus controller: Silicon Image, Inc. (formerly CMD > Technology Inc) SiI 3112 [SATALink/SATARaid] Serial ATA Controller (rev > 02) > 0000:03:00.0 VGA compatible controller: nVidia Corporation NV11 > [GeForce2 MX/MX 400] (rev b2) > > #*********************************************************** > > Distro is Debian Woody with all necessary packages backported in order > to have 2.6 working. > > I used postgres 7.4.3 to make some tests on a server which will go in > producton in a short time. > > The test was really simple: > > dropdb mydb > createdb mydb > time psql -U blus mydb <schema.sql > time psql -U blus mydb <data.sql > > #*********************************************************** > > I tried both 2.6.8.1 vanilla and 2.4.7 with -lck patches applied and run > the same test changing kernels. > > Tests were run: > - on a raid1 partition on 2 serial Ata disks (ext3) [software raid) > - on a non raid partition on /dev/sda0 (xfs) > > (only postgres data has been switched from raid-ext3 to xfs) > > > My purpose was merely have a difference of time between the 2 kernels in > performing that task. > > Case 1a is 2.4.27-lck1 with raid1 ext3 > Case 1b is 2.4.27-lck1 without raid on xfs > Case 2a is 2.6.8.1 with raid1 ext3 > Case 2b is 2.6.8.1 without raid on xfs > Results were: > > A) for creating the schema (which involves creating tables and indexes) > 1a: > real 0m1.312s > user 0m0.030s > sys 0m0.008s > 1b: > real 0m0.508s > user 0m0.024s > sys 0m0.012s > 2a: > real 0m0.941s > user 0m0.025s > sys 0m0.010s > 2b: > real 0m0.560s > user 0m0.024s > sys 0m0.005s > > B) to import the data (which implies both writing data to disk and > recalculating indexes) > 1a: > real 4m12.757s > user 0m3.376s > sys 0m1.700s > 1b: > real 1m0.467s > user 0m3.290s > sys 0m1.646s > 2a: > real 2m42.861s > user 0m3.590s > sys 0m1.523s > 2b: > real 1m30.746s > user 0m3.255s > sys 0m1.501s > > #********************************************** > HDPARM shows: > # hdparm -v > hdparm - get/set hard disk parameters - version v5.5 > > 2.4.7: > /dev/sda: > Timing buffer-cache reads: 2188 MB in 2.00 seconds = 1094.00 MB/sec > Timing buffered disk reads: 164 MB in 3.02 seconds = 54.34 MB/sec > > 2.6.8.1: > /dev/sda: > Timing buffer-cache reads: 2176 MB in 2.00 seconds = 1087.08 MB/sec > Timing buffered disk reads: 136 MB in 3.04 seconds = 44.77 MB/sec > > #********************************************** > It is my first experience with 2.6 branch kernels, because i am trying > to figure out if the tree is performing well to switch everithing in > production, so my ideas may be wrong... > > Raid tests may be faked because of the overhead caused by md sync (and > probably raid is better on 2.6). > However it seems that libsata has better performance on 2.4 (hdparm) > xfs tests shows that 2.4 has better performance if compared to 2.6 and > the difference, in my opinion, is not linked on libsata better > performance. > > What is your opinion ? > What can I try to improve performance ? >
I wouldn't worry too much about hdparm measurements. If you want to test the streaming throughput of the disk, run dd if=big-file of=/dev/null or a large write+sync.
Regarding your worse non-RAID XFS database results, try booting 2.6 with elevator=deadline and test again. If yes, are you using queueing (TCQ) on your disks? - 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/
| |