Re: Low CPU Usage

On 9/19/07, brauagustin-susc@yahoo.com.ar <brauagustin-susc@yahoo.com.ar> wrote:
>
>
> No, changing to fsync off didn't improve performance at all.
>
> Settings
> work_mem = 64MB
> max_stack_depth = 7MB #in the old server is 8MB but if I set in here give me
> the ulimit error
> max_fsm_pages = 204800
> effective_cache_size = 512MB
> Atuvacuum is off.
>
> I have run vacuum full and vacuum analyze. The databases are freezed (there
> are no insert, update or delete operations)!!!
> In both servers the query plans are identical with the same costs too!!!
>
> It's really weird, I don't see high values monitoring disk. Cpu usage is
> about 5% and sometimes a tips of 40 % of disk usage when the query is
> finishing (the first 3 minutes there are some tips of 11 to 16%).

(please don't top post)

This sounds like you've got problems somewhere in your I/O system.
hdparm etc may or may not be seeing the issue.  What do you see in
/var/log/messages or dmesg?