Ron Mayer wrote:
> Seems Linux has IO scheduling through a program called ionice.
>
> Has anyone here experimented with using it rather than
> vacuum sleep settings?
I looked at that briefly for smoothing checkpoints, but it was
unsuitable for that purpose because it only prioritizes reads, not writes.
It maybe worth trying for vacuum, though vacuum too can do a lot of
writes. In the worst case, the OS cache is saturated with dirty pages,
which blocks all writes in the system.
If it did prioritize writes as well, that would be *excellent*. Any
kernel hackers out there looking for a project?
--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com