Sujet : Re: RX2800 sporadic disk I/O slowdowns
De : ldo (at) *nospam* nz.invalid (Lawrence D'Oliveiro)
Groupes : comp.os.vmsDate : 21. Oct 2024, 01:28:30
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <vf477e$kfm0$4@dont-email.me>
References : 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
User-Agent : Pan/0.160 (Toresk; )
On Sun, 20 Oct 2024 20:13:50 -0400, Arne Vajhøj wrote:
On 10/20/2024 8:06 PM, Lawrence D'Oliveiro wrote:
>
On Sun, 20 Oct 2024 19:08:41 -0400, Arne Vajhøj wrote:
>
Let me try again.
>
DB write to plates & system crash => OK but slow
The DB knows how to make this fast. Remember its cache is faster than
any disk controller.
This is where the DB is writing to plates.
You can add a fourth scenario:
DB write to DB cache & system crash => guaranteed problem with
transaction
Transaction resilience is a standard thing with databases (and journalling
filesystems) going back decades.
Some DBMSes don’t even want to work through filesystems, they would rather
manage the raw storage themselves. This is why POSIX async I/O exists
<
https://manpages.debian.org/7/aio.7.en.html>.
RX2800 sporadic disk I/O slowdowns
Re: RX2800 sporadic disk I/O slowdowns