20
votes
1answer
241 views

Is it possible that just one bit switches so my file shows me a letter “Q” instead of a “S”

In our application we use Hibernate and PostgreSQL to store data. In one of our database tables we have a discriminator column which says for example "TIPPSPIEL". It is a fixed string and can not be ...
5
votes
3answers
2k views

PostgreSQL slow commit performance

We are having some problems with a PostgreSQL configuration. After some benchmarks I found out that very simple queries are taking a relatively long time, upon furter inspection it appears that the ...
6
votes
4answers
4k views

Postgres DISK IO very high. What can I do to reduce it immediately?

I'm aware faster disks than what I'm using will help but this will take longer to put in and I am trying to use some emergency measures to decrease disk IO. atop is reporting DSK usage on the red ...
1
vote
2answers
363 views

Server with a full disk! What can I do?

I have an Ubuntu server running PostgreSQL and a very light weight custom web-server. I knew this would happen but I was too busy, and now the disk has 0 bytes free. I don't need all the data in the ...
4
votes
2answers
443 views

choosing the right RAID level for PostgresQL database

I got an disk array appliance of 8 disks 1T each (UltraStor RS8IP4). It will be used solely by PostgresQL database and I am trying to choose the best RAID level for it. The most priority is for read ...
10
votes
3answers
2k views

Extremely Slow IO with Simple PostgreSQL 8.4.4 Queries on Centos 5.5

The strange and extremely slow IO pattern I'm seeing is this (output of iostat -dxk 1 /dev/xvdb1): Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm ...
2
votes
2answers
494 views

Which upgrade path for disk IO bound postgres server?

We currently have a Sun x4270 with 2xquad core Xeon Nehalmen 2.93ghz cores (16 threads), 72 gig of ram and 16 x 10k SAS disks split between the os raid 1, a partition for the Write Ahead Logs which is ...