From: | Moreno Andreo <moreno(dot)andreo(at)evolu-s(dot)it> |
---|---|
To: | PostgreSQL mailing lists <pgsql-general(at)postgresql(dot)org> |
Subject: | WAL directory size calculation |
Date: | 2016-07-28 13:25:18 |
Message-ID: | 4ccfe05f-7c31-8ca1-b43a-c961ac225736@evolu-s.it |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-general |
Hi folks! :-)
I'm about to bring up my brand new production server and I was wondering
if it's possible to calculate (approx.) the WAL directory size.
I have to choose what's better in terms of cost vs. performance (we are
on Google Cloud Platform) between a ramdisk or a separate persistent
disk. Obviously ramdisk will be times faster disk, but having a, say,
512 GB ramdisk will be a little too expensive :-)
I've read somewhere that the formula should be 16 MB * 3 *
checkpoint_segment in size. But won't it be different depending on the
type of /wal_level/ we set? And won't it also be based on the volume of
transactions in the cluster?
And, in place of not-anymore-used-in-9.5 /checkpoint_segment/ what
should I use? /max_wal_size/?
Aside of this, I'm having 350 DBs that sum up a bit more than 1 TB, and
plan to use wal_level=archive because I plan to have a backup server
with barman.
Using the above formula I have:
16 MB * 3 * 1 GB
that leads to to ... uh .. 48000 TB?
Any ideas?
Thanks
Moreno.-
From | Date | Subject | |
---|---|---|---|
Next Message | David G. Johnston | 2016-07-28 13:33:25 | Re: WAL directory size calculation |
Previous Message | Gavin Flower | 2016-07-28 08:18:13 | Re: Uber migrated from Postgres to MySQL |