|
Hi Will, Yes, I think we’ve seen some discussions on that. Our servers our hosted on Amazon Ec2 and upgrading the kernel does not seem so straight forward. We did a benchmark using pgbench on 3.5 vs 3.2 and saw an improvement. Unfortunately our production server would not boot off 3.5 so we had to revert back to 3.2. At this point we are contemplating whether it’s better to go back to 11.04 or upgrade to 12.10 (which comes with kernel version 3.5). Any thoughts on that would be appreciated. Dan From: Will Ferguson [mailto:WFerguson@xxxxxxxxxxxxxxx] Hey Dan, If I recall correctly there were some discussions on here related to performance issues with the 3.2 kernel. I'm away at the moment so can't dig them out but there have been much discussions lately about kernel performance in 3.2 which don't seem present in 3.4. I'll see if I can find them when I'm next at my desk. Will Sent from Samsung Mobile
Thanks for the reply. We are still using postgresql-9.0-801.jdbc4.jar. It seemed to us that this is more related to the OS than the JDBC, version as we had the issue before we upgraded to 9.2. It might still be worth a try. Just out of curiosity, has anyone else experienced performance issues (or even tried) with the 9.0 jdbc driver against 9.2 server? Dan From: Eric Haertel [mailto:eric.haertel@xxxxxxxxxxx] I don't know if it helps, but I had after update from 8.4 to 9.1 extrem problems with my local test until I changed the JDBC driver to the propper version. I'm not shure if the load occured on the client or the server side as the local integration test run on my machine. 2013/2/12 Dan Kogan <dan@xxxxxxxxxx> Hello, We upgraded from Ubuntu 11.04 to Ubuntu 12.04 and almost immediately obeserved increased CPU usage and significantly higher load average on our database server. At the time we were on Postgres 9.0.5. We decided to upgrade to Postgres 9.2 to see if that resolves the issue, but unfortunately it did not. Just for illustration purposes, below are a few links to cpu and load graphs pre and post upgrade. https://s3.amazonaws.com/iqtell.ops/Load+Average+Post+Upgrade.png https://s3.amazonaws.com/iqtell.ops/Load+Average+Pre+Upgrade.png https://s3.amazonaws.com/iqtell.ops/Server+CPU+Post+Upgrade.png https://s3.amazonaws.com/iqtell.ops/Server+CPU+Pre+Upgrade.png We also tried tweaking kernel parameters as mentioned here - http://www.postgresql.org/message-id/50E4AAB1.9040902@xxxxxxxxxxxxxxxx, but have not seen any improvement. Any advice on how to trace what could be causing the change in CPU usage and load average is appreciated. Our postgres version is: PostgreSQL 9.2.2 on x86_64-unknown-linux-gnu, compiled by gcc (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3, 64-bit OS: Linux ip-10-189-175-25 3.2.0-37-virtual #58-Ubuntu SMP Thu Jan 24 15:48:03 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux Hardware (this an Amazon Ec2 High memory quadruple extra large instance): 8 core Intel(R) Xeon(R) CPU E5-2665 0 @ 2.40GHz 68 GB RAM RAID10 with 8 drives using xfs Drives are EBS with provisioned IOPS, with 1000 iops each Postgres Configuration: archive_command = rsync -a %p slave:/var/lib/postgresql/replication_load/%f archive_mode = on checkpoint_completion_target = 0.9 checkpoint_segments = 64 checkpoint_timeout = 30min default_text_search_config = pg_catalog.english external_pid_file = /var/run/postgresql/9.2-main.pid lc_messages = en_US.UTF-8 lc_monetary = en_US.UTF-8 lc_numeric = en_US.UTF-8 lc_time = en_US.UTF-8 listen_addresses = * log_checkpoints=on log_destination=stderr log_line_prefix = %t [%p]: [%l-1] log_min_duration_statement =500 max_connections=300 max_stack_depth=2MB max_wal_senders=5 shared_buffers=4GB synchronous_commit=off unix_socket_directory=/var/run/postgresql wal_keep_segments=128 wal_level=hot_standby work_mem=8MB Thanks, Dan
Eric Härtel Tel.: +49 (0) 30 240 20 40 35 Mobil: +49 (0) 174 43 38 614
Groupon GmbH & Co. Service KG | Oberwallstraße 6 | 10117 Berlin Geschäftsführer: Mark S. Hoyt | Bradley Downes | Daniel Köllner |
