Hi Martijn, hi Greg,
thanks you very much for your help. We finally got rid of these annoying
spikes.
First we tried to set
checkpoint_segments = 3# before 16
checkpoint_timeout = 5min # before: 60min
which didn't really help.
we had the same spikes but more often. Then we tried to lo
On Thu, Jun 10, 2010 at 04:00:54PM -0400, Greg Smith wrote:
>> 5. Does anybody know if I can set dirty_background_ratio to 0.5? As we
>> have 12 GB RAM and rather slow disks 0,5% would result in a maximum of
>> 61MB dirty pages.
>
> Nope. Linux has absolutely terrible controls for this critic
Janning wrote:
most docs I found relates to 8.2 and 8.3. In Things of checkpoints, is 8.4
comparable to 8.3? It would be nice if you update your article to reflect 8.4
There haven't been any changes made in this area since 8.3, that's why
there's been no update. 8.4 and 9.0 have exactly the s
On Thursday 10 June 2010 22:00:54 Greg Smith wrote:
> Janning wrote:
> > 1. With raising checkpoint_timeout, is there any downgrade other than
> > slower after-crash recovery?
>
> Checkpoint spikes happen when too much I/O has been saved up for
> checkpoint time than the server can handle. While t
Janning wrote:
1. With raising checkpoint_timeout, is there any downgrade other than slower
after-crash recovery?
Checkpoint spikes happen when too much I/O has been saved up for
checkpoint time than the server can handle. While this is normally
handled by the checkpoint spreading logic,
On Thu, Jun 10, 2010 at 12:49 PM, Janning wrote:
> 1. With raising checkpoint_timeout, is there any downgrade other than slower
> after-crash recovery?
Depends on how busy your DB is, and how many checkpoint segments you
have. All the timeout does is say, "if we have not done a checkpoint
this l
Hi again,
nobody answered my question :-(, so i did some research. I was convinced to
set:
checkpoint_segments = 16
checkpoint_timeout = 60min
and
echo 2 > /proc/sys/vm/dirty_background_ratio
this helped a lot. Our freeze time was reduced from 10 seconds to 5 seconds.
But this is still way to
Hi,
we currently encounter an increasing load on our website. With the increasing
load we see some problems on our database. so we checked what happens and we
saw spikes in our load when checkpoints are about to finish.
Our configuration:
max_connections = 125
ssl = false
shared_buffers = 500M
