Re: ATA disk performance (ICH2 controller), some tests andcomparison with Linux 2.6.5

Michael Nottebrock wrote:
> On Sunday 26 September 2004 12:50, Doug Russell wrote:
> 
>>On Sun, 26 Sep 2004, Michael Nottebrock wrote:
>>
>>>On Saturday 25 September 2004 23:45, Jeremy Chadwick wrote:
>>>
>>>>6)  I'm still amazed people have systems in production that use ICH2.
>>>>AFAIK, the chipset is deprecated.
>>>
>>>Eh? i845-based motherboards were not exactly a niche product and are not
>>>very ancient either. I'm surprised it surprises you to see them used. :-)
>>
>>Bah!  Just because some hardware is common does not mean is is good!
> 
> 
> Supporting and being used on common-but-not-so-good hardware is one of the 
> best (and oldest) traditions of FreeBSD. :-)

Yeah, well, we try, my last ich2 based system died long ago so it makes 
it harder to keep support top notch :)

Anyhow, please try the below patch and let me know if that changes 
behavior in anyway.

BTW, you need to compare speeds of the *exact same* area of the disk(s). 
Modern disk often has only half the transfer rate on the last 1/3 of the 
platters..

diff -u -r1.88 ata-chipset.c
--- ata-chipset.c       10 Sep 2004 10:31:37 -0000      1.88
+++ ata-chipset.c       26 Sep 2004 12:08:56 -0000
_at__at_ -976,6 +976,8 _at__at_
         pci_write_config(parent, 0x48, reg48 & ~(0x0001 << devno), 2);
         pci_write_config(parent, 0x4a, (reg4a & ~(0x3 << (devno << 
2))), 2);
      }
+
+    reg54 |= 0x0400;
      if (mode >= ATA_UDMA2)
         pci_write_config(parent, 0x54, reg54 | (0x1 << devno), 2);
      else


-- 

-Søren