Re: 5.3-RC1 poor ATA perfomance

Alexander S. Usov wrote:

> Hi!
> 
> I have hit a very strange problem with a poor ata perfomance.
> 
> First some numbers:
> === FreeBSD 5.3-RC1
> # dd if=/dev/ad0 of=/dev/null bs=1m count=512
> 536870912 bytes transferred in 23.891834 secs (22470896 bytes/sec)
> # dd if=/dev/zero of=/dev/ad0s1 bs=1m count=512
> 536870912 bytes transferred in 35.413467 secs (15160078 bytes/sec)
> 
> === Linux 2.6.8-1 (OpenBSD also gives similar numbers)
> # dd if=/dev/hda of=/dev/null bs=1M count=512
> 536870912 bytes transferred in 22.272891 seconds (24104231 bytes/sec)
> # dd if=/dev/zero of=/dev/hda1 bs=1M count=512
> 536870912 bytes transferred in 23.574157 seconds (22773706 bytes/sec)
> 
> As you see the writing is quite slower.
> 
> Some details on hardware:
> atapci0: <Intel ICH4 UDMA100 controller> port 0x1860-0x186f,0x376,
> 0x170-0x177,0x3f6,0x1f0-0x1f7 at device 31.1 on pci0
> ata0: channel #0 on atapci0
> ad0: 38154MB <TOSHIBA MK4021GAS/GA224A> [77520/16/63] at ata0-master UDMA100
> 
> ad1 is absent.
> 

Arrrggghhhh, please not all over again.

We've just sort of terminated the previous thread about this:
   http://lists.freebsd.org/pipermail/freebsd-current/2004-October/040474.html
And it is a LONG thread.

One of the more essentail remarks made bij PHK was that this type of testing 
is close to no use/good. And to be honest: previously discussed number were 
even worse. And were probably dues to hardware which was designed/backed on 
monday-morning.
First problem is that you need to determine what you want to do with your system.

Please read the thread.

--WjW