On 3/27/2011 10:43 PM, Tom Lane wrote:
In particular, I thought the direction Jan was headed was to release and
reacquire the lock between truncating off limited-size chunks of the
file. If we do that, we probably *don't* want or need to allow autovac
to be booted off the lock more quickly.
That is correct.
3) Scanning backwards 8MB at a time scanning each 8MB forwards instead
of just going back by block backwards.
Maybe. I'd want to see some experimental evidence justifying the choice
of chunk size; I'm pretty sure this will become counterproductive once
the chunk size is too large.
Me too, which is why that part of my proposal is highly questionable and
requires a lot of evidence to be even remotely considered for back releases.
Jan
--
Anyone who trades liberty for security deserves neither
liberty nor security. -- Benjamin Franklin
--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers
