On Fri, 10 Mar 2000, Paul Jakma wrote:
> On Thu, 9 Mar 2000, Kent Nilsen wrote:
>
> Just installed a new server (PIII 600, 392Mb RAM, Mylex
> ExtremeRAID (DAC1164P, 64Mb Cache), Mandrake 7.0, 2.2.14,
> 2.2.5 patch for DAC960)
>
> some of those figures are a bit off, esp the first few cause the
> filesize used is much less than RAM so you'd be testing RAM more than
> disk.
>
> Also, should I test with the -W option, will Linux
> write like this when using it as a NFS/Samba only? Here are the
> Tiotest (latest) results:
>
With -W option in tiotest/tiobench the writes will be sequential.
Second writing thread will wait first one to finish first and so on.
So in effect this is a useless way to test parallel IO performance
on write side.
But what it is for is that this way when only one thread is allowed
to write in time, the test files will not be fragmented across disk
area. This makes a difference atleast in raid1 READ case when you want
to measure concurrent potential read performance.
So the -W could be translated as, '-Write avoiding fragmentation'
The default behaviour of tiobench/tiotest should be that it is off.
(after all its name says it should test concurrent io :)
I have to check if this is the case.
-- Mika <[EMAIL PROTECTED]>
