You could archive the data as you perform the
dump
pg_dump <your options> | bzip2
> filename.bz2
bzip2 offers an excellent compression and you
could end up with an archive with less than 10GB
Later you can reload that into another db on
a different server
-----Original
Message-----
From:
pgsql-admin-owner@xxxxxxxxxxxxxx [mailto:pgsql-admin-owner@xxxxxxxxxxxxxx] On Behalf Of Steve Burrows
Sent: Friday, April 28, 2006 11:58 AM
To: pgsql-admin@xxxxxxxxxxxxxx
Subject: [ADMIN] Backing up large
databases
I am
struggling to find an acceptable way of backing up a PostgreSQL 7.4 database.
The database is quite large, currently it occupies about 180GB, divided into
two elements, a set of active tables and a set of archive tables which are only
used for insertions.
I ran pg_dump -Fc recently, it took 23.5 hours to run, and output a single file
of 126GB. Obviously as the database continues to grow it will soon be so large
that it cannot be pg_dumped within a day. Running rsync to do a complete fresh
copy of the pgsql file structure took 4 hours, but later that day running
another iteration of rsync (which should have only copied changed files) took 3
hours, and I cannot afford to have the db down that long.
Anybody with any ideas? The database is being used as the backend for a mail
server, so it has transactions 24 hours a day but is quieter at night. I want
to be able to back it up or replicate it on a daily basis with minimum downtime
so that the mail backlog doesn't get too large. Ideally I want the first
generation of backup/replica going onto the same machine as the original
because the volume of data is such that any attempt at network or tape backup
of the live files will require too much downtime, once I've got a backup then I
can copy that out to other NAS or tape at leisure.
If anyone has experience of safeguarding a similarly large PostgreSQL database
with minimal downtime I'd be delighted to hear.. The machine is running 2
Xeons, 4GB ram and a half-terabyte RAID10 array on a DELL PERC scsi subsystem,
with a load average of around 0.5 - 0.6, so it's not exactly overstretched.
Thanks,
Steve
