Thread: [GENERAL] pg_xlog keeps growing
Hi,
I have a postgres cluster running in hot_standby. I see the pg_xlog is growing over time (may files of size 16 MB each). The replication lag is very less ~2kB, and never goes into a bad state.
I'm manually resetting this once a while using pg_resetxlog command.
Is there a way to understand why my system keeps running into this problem ?
Thanks
> On Feb 27, 2017, at 8:33 PM, dhanuj hippie <dhanuj.hippie@gmail.com> wrote: > > Hi, > > I have a postgres cluster running in hot_standby. I see the pg_xlog is growing over time (may files of size 16 MB each).The replication lag is very less ~2kB, and never goes into a bad state. > I'm manually resetting this once a while using pg_resetxlog command. > Is there a way to understand why my system keeps running into this problem ? > > Thanks wal_keep_segments is set to ??? (and version = ???, etc)
psql (9.3.5)
wal_keep_segments = 1024
On Tue, Feb 28, 2017 at 9:16 AM, Rob Sargent <robjsargent@gmail.com> wrote:
wal_keep_segments is set to ???
> On Feb 27, 2017, at 8:33 PM, dhanuj hippie <dhanuj.hippie@gmail.com> wrote:
>
> Hi,
>
> I have a postgres cluster running in hot_standby. I see the pg_xlog is growing over time (may files of size 16 MB each). The replication lag is very less ~2kB, and never goes into a bad state.
> I'm manually resetting this once a while using pg_resetxlog command.
> Is there a way to understand why my system keeps running into this problem ?
>
> Thanks
(and version = ???, etc)
So does it work like - it can go upto 16MB*1024 times which is 16GB, and then this will be cleaned up automatically ?
On Tue, Feb 28, 2017 at 9:47 AM, dhanuj hippie <dhanuj.hippie@gmail.com> wrote:
psql (9.3.5)wal_keep_segments = 1024On Tue, Feb 28, 2017 at 9:16 AM, Rob Sargent <robjsargent@gmail.com> wrote:wal_keep_segments is set to ???
> On Feb 27, 2017, at 8:33 PM, dhanuj hippie <dhanuj.hippie@gmail.com> wrote:
>
> Hi,
>
> I have a postgres cluster running in hot_standby. I see the pg_xlog is growing over time (may files of size 16 MB each). The replication lag is very less ~2kB, and never goes into a bad state.
> I'm manually resetting this once a while using pg_resetxlog command.
> Is there a way to understand why my system keeps running into this problem ?
>
> Thanks
(and version = ???, etc)
On Tue, Feb 28, 2017 at 1:20 PM, dhanuj hippie <dhanuj.hippie@gmail.com> wrote: > So does it work like - it can go upto 16MB*1024 times which is 16GB, and > then this will be cleaned up automatically ? On a standby each time a restart point is created the oldest segments are either recycled or removed, wal_keep_segments retains more of that. You can look at KeepLogSeg() in src/backend/access/transam/xlog.c if you want.. -- Michael
Based on my config, what is the max size this directory is expected to grow ? And how can I check whether this recycle/removal is happening fine ?
On Tue, Feb 28, 2017 at 10:08 AM, Michael Paquier <michael.paquier@gmail.com> wrote:
On Tue, Feb 28, 2017 at 1:20 PM, dhanuj hippie <dhanuj.hippie@gmail.com> wrote:
> So does it work like - it can go upto 16MB*1024 times which is 16GB, and
> then this will be cleaned up automatically ?
On a standby each time a restart point is created the oldest segments
are either recycled or removed, wal_keep_segments retains more of
that. You can look at KeepLogSeg() in
src/backend/access/transam/xlog.c if you want..
--
Michael
On Monday, February 27, 2017, dhanuj hippie <dhanuj.hippie@gmail.com> wrote:
So does it work like - it can go upto 16MB*1024 times which is 16GB, and then this will be cleaned up automatically ?On Tue, Feb 28, 2017 at 9:47 AM, dhanuj hippie <dhanuj.hippie@gmail.com> wrote:psql (9.3.5)wal_keep_segments = 1024
David J.