On Mon, 20 Jun 2005, Bruce Evans wrote: |On Thu, 16 Jun 2005 [EMAIL PROTECTED] wrote: | |> This was first posted on freebsd-question, but I could not find |> the solution yet. |> Maybe you could help me. | |Maybe a little. I don't use 5.4...
It happens on 5.3 also. Not tested on 4.x. |> I´ve installed FreeBSD 5.4 on a new machine with the following |> hardware: |> |> Asus P4P800 SE (BIOS v. 1008) |> 2GB RAM ( 4x 512 DDR400 ) |> 2 HDD Samsung SP0802N (80GB 7200rpm ata-100) 80 pins cable. |> |> The HD were formated with newfs defaults, and the following |> results were the same using both as master (primary e secondary) or with a |> master / slave (same interface). |> |> With diskinfo both performance are the same, but with "dd", the |> second disc (the slave or the secondary master), is always worst as if it |> were working in DMA2. | |I remember a commit to the ata driver to fix misprogramming of DMA timing |on an Intel chipset for devices and/or channels other than the first. I'm |not sure if 5.4 has the bug or the fix. It seems that the bug is still there. |diskinfo only tests reading, and you only showed a dd test using writing |(to a file), so the problem is apparently only that writing to the second |drive is slow. Right. |> what should be the right results? | |Swap the devices to see if it is a drive problem (unlikely with the |same model of drive but... I have one system that apparently has |worse timing on the secondary channel. This showed up as writes |causing subsequent reads to be slow -- apparently the writes caused |some errors and error correction as perfect except for slowing things |down). I´d already did it. It´s not a hardware problem. Always happen on the second drive, no matter which is it. - Marcelo _______________________________________________ freebsd-performance@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-performance To unsubscribe, send any mail to "[EMAIL PROTECTED]"