| From: | Merlin Moncure <mmoncure(at)gmail(dot)com> |
|---|---|
| To: | James Sewell <james(dot)sewell(at)jirotech(dot)com> |
| Cc: | pgsql-general <pgsql-general(at)postgresql(dot)org> |
| Subject: | Re: PostgreSQL corruption |
| Date: | 2017-02-16 14:25:05 |
| Message-ID: | CAHyXU0yWX0VHgDmeOp5nGYophczxwR=o89ND8pcSxkDehvot_Q@mail.gmail.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-general |
On Tue, Feb 14, 2017 at 7:23 PM, James Sewell <james(dot)sewell(at)jirotech(dot)com>
wrote:
> OK,
>
> So with some help from the IRC channel (thanks macdice and JanniCash)
> it's come to light that my RAID1 comprised of 2 * 7200RPM disks is
> reporting ~500 ops/sec in pg_test_fsync.
>
> This is higher than the ~120 ops/sec which you would expect from 720RPM
> disks - therefore something is lying.
>
> Breaking up the RAID and re-imaging with JBOD dropped this to 50 ops/sec -
> another question but still looking like a real result.
>
> So in this case it looks like the RAID controller wasn't disabling caching
> as advertised.
>
yup -- that's the thing. Performance numbers really tell the whole (or at
least most-) of the story. If it's too good to be true, it is. These
days, honestly I'd just throw out the raid controller and install some
intel ssd drives.
merlin
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Adrian Klaver | 2017-02-16 14:25:50 | Re: Alternate way of xpath |
| Previous Message | JP Jacoupy | 2017-02-16 13:57:52 | Service configuration file and password security |