Yes, did you perhaps have a long running query that was doing lots of sorts, if so it creates as many 1 GB temp files as it takes to complete the sort, and they go into your data partition by default. Once the query completes, postgres cleans them up.
From: pgsql-admin-owner@postgresql.org [mailto:pgsql-admin-owner@postgresql.org] On Behalf Of Thomas SIMON
Sent: Thursday, October 24, 2013 9:21 AM
To: pgsql-admin@postgresql.org
Subject: [ADMIN] Huge increase of database partition
Hi the list,
Yesterday, i have had a big problem of disk space on my server, running postgresql 9.0.13; with streaming replication.
Between 6pm and 7-30pm, i went from 45% used space to 99% (100% ?) used space on my /data partition (who contains my postgresql/9.0/main/base ; but does not contains the WAL; they are deported on an other partition). - seen only after with munin -
Juste after that - still according to munin- , the partition suddently decreases to its normal value (around 45%)
This peak represents around 165 Go of data ! ; beacause my partition size is 315 Go.
I can't explain why, it's the first time i have something like this. Usually, the size of the partition is very stable ; and grows very slowly.
Still with munin, i see that in this period, the blocks read per second increases from around 20k to 80k, and i see that the disk utilisation is around 100%, which confirms that postgres wrote a lot of data.
I don't understand how this can happen, have you ever seen things like this ?
Thanks in advance,
Thomas