Did anybody else notice this? The result of "hdparm -t" under 2.6.20-rc seems to be less than half of what you get on 2.6.19. However, disk I/O did *not* get slower according to bonnie++.
That is, there is no harm beyond confusion of the user. hdparm is lying for some reason. Below is the output of hdparm v6.6 and bonnie++ 1.93c. I ran hdparm 3 times each and bonnie++ 2 times to ensure that I get typical readings, on an otherwise idle system. hdparm -tT /dev/???: ======================================================================== 2.6.19.1, IDE: Timing cached reads: 10728 MB in 2.00 seconds = 5371.95 MB/sec Timing buffered disk reads: 154 MB in 3.01 seconds = 51.11 MB/sec 2.6.19.1, SATA: Timing cached reads: 8028 MB in 2.00 seconds = 4017.69 MB/sec Timing buffered disk reads: 220 MB in 3.01 seconds = 73.18 MB/sec 2.6.19.1 + latest 1394 drivers, FireWire 800: Timing cached reads: 10216 MB in 2.00 seconds = 5114.73 MB/sec Timing buffered disk reads: 214 MB in 3.03 seconds = 70.71 MB/sec 2.6.19.1 + latest 1394 drivers, FireWire 400: Timing cached reads: 8892 MB in 2.00 seconds = 4449.76 MB/sec Timing buffered disk reads: 74 MB in 3.08 seconds = 24.02 MB/sec ======================================================================== 2.6.20-rc3, IDE: Timing cached reads: 11492 MB in 2.00 seconds = 5753.76 MB/sec Timing buffered disk reads: 56 MB in 3.10 seconds = 18.09 MB/sec 2.6.20-rc3, SATA: Timing cached reads: 10736 MB in 2.00 seconds = 5374.70 MB/sec Timing buffered disk reads: 102 MB in 3.00 seconds = 33.99 MB/sec 2.6.20-rc3 + latest 1394 drivers, FireWire 800: Timing cached reads: 9476 MB in 2.00 seconds = 4742.33 MB/sec Timing buffered disk reads: 70 MB in 3.08 seconds = 22.69 MB/sec 2.6.20-rc3 + latest 1394 drivers, FireWire 400: Timing cached reads: 10336 MB in 2.00 seconds = 5173.65 MB/sec Timing buffered disk reads: 40 MB in 3.09 seconds = 12.95 MB/sec ======================================================================== bonnie++ on the SATA disk with a single 47% filled reiserfs partition: ======================================================================== 2.6.19.1, SATA: > Version 1.93c ------Sequential Output------ --Sequential Input- > --Random- > Concurrency 1 -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- > --Seeks-- > Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec > %CP > stein 2G 203 99 57389 18 26943 9 856 93 66032 17 190.8 > 6 > Latency 48553us 295ms 1130ms 196ms 18075us 500ms > Version 1.93c ------Sequential Create------ --------Random > Create-------- > stein -Create-- --Read--- -Delete-- -Create-- --Read--- > -Delete-- > files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec > %CP > 16 16541 55 +++++ +++ 18794 71 22933 79 +++++ +++ 24005 > 95 > Latency 107ms 129us 175ms 16613us 76us 236us That is, 56.0 MB/s write and 64.5 MB/s read performance of sequential block I/O. ======================================================================== 2.6.20-rc3, SATA: > Version 1.93c ------Sequential Output------ --Sequential Input- > --Random- > Concurrency 1 -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- > --Seeks-- > Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec > %CP > stein 2G 210 99 57340 18 26920 10 1166 89 66805 17 195.3 > 5 > Latency 47794us 284ms 869ms 249ms 36229us 533ms > Version 1.93c ------Sequential Create------ --------Random > Create-------- > stein -Create-- --Read--- -Delete-- -Create-- --Read--- > -Delete-- > files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec > %CP > 16 19645 67 +++++ +++ 21767 83 26951 94 +++++ +++ 24859 > 98 > Latency 231ms 85us 120us 469us 69us 118us That is, 56.0 MB/s write and 65.2 MB/s read performance of sequential block I/O. ======================================================================== It's a 32bit kernel on a dual core x86 PC: > $ uname -a > Linux stein 2.6.20-rc3 #7 SMP PREEMPT Sat Jan 6 17:07:30 CET 2007 i686 > Intel(R) Core(TM)2 CPU T7200 @ 2.00GHz GenuineIntel GNU/Linux The motherboard is i945GT based. > $ /usr/sbin/lspci > 00:00.0 Host bridge: Intel Corporation Mobile Memory Controller Hub (rev 03) > 00:01.0 PCI bridge: Intel Corporation Mobile PCI Express Graphics Port (rev > 03) > 00:02.0 VGA compatible controller: Intel Corporation Mobile Integrated > Graphics Controller (rev 03) > 00:1b.0 Class 0403: Intel Corporation 82801G (ICH7 Family) High Definition > Audio Controller (rev 01) > 00:1c.0 PCI bridge: Intel Corporation 82801G (ICH7 Family) PCI Express Port 1 > (rev 01) > 00:1c.4 PCI bridge: Intel Corporation 82801GR/GH/GHM (ICH7 Family) PCI > Express Port 5 (rev 01) > 00:1d.0 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI #1 > (rev 01) > 00:1d.1 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI #2 > (rev 01) > 00:1d.2 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI #3 > (rev 01) > 00:1d.3 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI #4 > (rev 01) > 00:1d.7 USB Controller: Intel Corporation 82801G (ICH7 Family) USB2 EHCI > Controller (rev 01) > 00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev e1) > 00:1f.0 ISA bridge: Intel Corporation 82801GB/GR (ICH7 Family) LPC Interface > Bridge (rev 01) > 00:1f.1 IDE interface: Intel Corporation 82801G (ICH7 Family) IDE Controller > (rev 01) > 00:1f.2 IDE interface: Intel Corporation 82801GB/GR/GH (ICH7 Family) Serial > ATA Storage Controllers cc=IDE (rev 01) > 00:1f.3 SMBus: Intel Corporation 82801G (ICH7 Family) SMBus Controller (rev > 01) > 01:00.0 PCI bridge: Texas Instruments Unknown device 8231 (rev 03) > 02:02.0 FireWire (IEEE 1394): Texas Instruments TSB82AA2 IEEE-1394b Link > Layer Controller (rev 01) > 04:00.0 Ethernet controller: Intel Corporation 82573L Gigabit Ethernet > Controller > 05:04.0 FireWire (IEEE 1394): VIA Technologies, Inc. IEEE 1394 Host > Controller (rev 80) The IDE disk is a Hitachi HTE721010G9AT00 7200rpm 2.5". The SATA disk is a Seagate ST3750640AS 7200rpm 3.5". The FireWire disk is a dual ST3400832A 7200rpm 3.5" stripe-set on OXFW921, tested on the 1394b and the 1394a controller. Config is basically the same under both kernels: http://me.in-berlin.de/~s5r6/linux1394/work-in-progress/other_stuff/config-diff-2.6.19.1--2.6.20-rc3-20070106.txt http://me.in-berlin.de/~s5r6/linux1394/work-in-progress/other_stuff/config-2.6.20-rc3-20070106.txt Userland is Gentoo 2006.1, kernel is Linus's with FireWire driver patches. -- Stefan Richter -=====-=-=== ---= --==- http://arcgraph.de/sr/ - 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/
