Hendrik van den Boogaard wrote:
> Copy the large files in one window (PATA -> SATA) and do a 'find /'
> (SATA drive) in the other window. I found out that the 'find' command is
> a *lot* more responsive pushing file names to the screen when I put the
> NCQ buffer on 1 item (effectively disabling NCQ). The mouse and cursor
> still lock up often for less than a second and performance is still
> sluggish but the machine is not completely unusable. While I am typing
> this I put the NCQ setting back to 31 as it was on before but now I
> cannot even type this complete sentence without seeing it appear on the
> screen.
That's quite surprising: NCQ should in theory always make it faster,
unless you have a terrible drive implementation.
> As far as I can remember somewhere in the 2.6.1x kernels NCQ was
> added together with all the new libata stuff (that's for me when a lot
> of trouble started; a bad sector on a disk created kernel-oopses on
> another NVidia based computer with a 4TB software Raid5 Array). This
> might also explain why I have not seen this problem before as my old
> 160G drive is PATA and has no NCQ.
Both of these things (the oopses and the NCQ reduction in performance)
ought to be reported to Linux's libata maintainer...
Hendrik van den Boogaard wrote:
> Copy the large files in one window (PATA -> SATA) and do a 'find /'
> (SATA drive) in the other window. I found out that the 'find' command is
> a *lot* more responsive pushing file names to the screen when I put the
> NCQ buffer on 1 item (effectively disabling NCQ). The mouse and cursor
> still lock up often for less than a second and performance is still
> sluggish but the machine is not completely unusable. While I am typing
> this I put the NCQ setting back to 31 as it was on before but now I
> cannot even type this complete sentence without seeing it appear on the
> screen.
That's quite surprising: NCQ should in theory always make it faster,
unless you have a terrible drive implementation.
> As far as I can remember somewhere in the 2.6.1x kernels NCQ was
> added together with all the new libata stuff (that's for me when a lot
> of trouble started; a bad sector on a disk created kernel-oopses on
> another NVidia based computer with a 4TB software Raid5 Array). This
> might also explain why I have not seen this problem before as my old
> 160G drive is PATA and has no NCQ.
Both of these things (the oopses and the NCQ reduction in performance)
ought to be reported to Linux's libata maintainer...
-- Jamie