Hello John,
> To add a data point to this debate, I have two identical Solaris 7
> machines with identical diskpacks on them. On one I have striped up the 6
> disks and am using a logging filesystem using ODS. On the other I'm using
> the logging filesystem now part of Solaris on each of the 6 disks mounted
> as separate cache directories.
>
> The performance difference between the two machines at their current
> loading is negligable. Therefore the benefit of not loosing all your
> cache when you blow or add disk is probably as good a reason as another
> for chosing multiple cachedirs.
>
But that may count only, if disk I/O already is the or one of the
bottlenecks on at least at one of your systems.
It's quite the same at our systems: currently we are running one with
async-io and the other one without this option, both configured with
a big stripe of 5 disks.
At the current load we mostly see no performance differences.
Jan
