[ltp] Problems with disc-performance and libata

Oli linux-thinkpad@linux-thinkpad.org
Wed, 22 Aug 2007 11:48:22 +0200


Hi,

I'm using a Lenovo Thinkpad with TOSHIBA MK1234GS HD and MATSHITA
DVD-RAM UJ-850 on 82801GBM/GHM (ICH7 Family) Serial ATA Storage
Controller IDE. The Kernel is a 2.6.22.1 from Kernel.org. I'm using
Ubuntu FF.

sudo hdparm -t /dev/scd0 gives 

Timing buffered disk reads:    2 MB in  4.47 seconds = 457.75 kB/sec

sudo hdparm -t /dev/sda gives

Timing buffered disk reads:  102 MB in  3.04 seconds =  33.51 MB/sec

which is a quite poor performance and makes any streaming impossible.
Obviously UDMA is working correctly as dmesg | grep UDMA says:

[   43.636590] ata1: SATA max UDMA/133 cmd 0xffffc20004612500 ctl
0x0000000000000000 bmdma 0x0000000000000000 irq 314
[   43.636595] ata2: SATA max UDMA/133 cmd 0xffffc20004612580 ctl
0x0000000000000000 bmdma 0x0000000000000000 irq 314
[   43.636599] ata3: SATA max UDMA/133 cmd 0xffffc20004612600 ctl
0x0000000000000000 bmdma 0x0000000000000000 irq 314
[   43.636603] ata4: SATA max UDMA/133 cmd 0xffffc20004612680 ctl
0x0000000000000000 bmdma 0x0000000000000000 irq 314
[   44.177980] ata1.00: ATA-7: TOSHIBA MK1234GSX, AH002E, max UDMA/100
[   44.179192] ata1.00: configured for UDMA/100
[   44.326918] ata5: PATA max UDMA/133 cmd 0x00000000000101f0 ctl
0x00000000000103f6 bmdma 0x0000000000011880 irq 14
[   44.326922] ata6: PATA max UDMA/133 cmd 0x0000000000010170 ctl
0x0000000000010376 bmdma 0x0000000000011888 irq 15
[   44.571970] ata5.00: ATAPI: MATSHITADVD-RAM UJ-850, RB01, max UDMA/33
[   44.738552] ata5.00: configured for UDMA/33
[    0.610332] ata5.00: configured for UDMA/33
[    0.750296] ata1.00: configured for UDMA/100

Is there any solution for that problem or at least a workaround?
Ubuntu-maintainers won't fix that soon:

https://bugs.launchpad.net/ubuntu/+source/linux-source-2.6.22/+bug/110636

I also tried to recompile the kernel as recommended in the official
libata-faq ( http://linux-ata.org/faq.html ) but the system stuck when
booting the root-partition. Booting with combined_mode=libata or
combined_mode=ide didn't affect the performance, too.  

Thanks in advance,

Oli