Thread: meaning of (to prevent wraparound) ..??
Hi, I have autovacuum running in background from last 30-40 minutes but I noticed that it is with "(to prevent wraparound)" say for example autovacuum: VACUUM trk.move (to prevent wraparound). So what is the meaning of "(to prevent wraparound)" here ? Will it impact the autovacuum anyhow ? Please help me. Regards, Atul
Hi Atul,
This means autovacuum is doing it’s job — most likely no need to be alarmed here based on this alone. The autovacuum is helping avoid a txid limit. This is part of PostgreSQL MVCC. You may check that section of the documentation for more information on this.
On Wed, Nov 25, 2020 at 22:54 Atul Kumar <akumar14871@gmail.com> wrote:
Hi,
I have autovacuum running in background from last 30-40 minutes but I
noticed that it is with "(to prevent wraparound)" say for example
autovacuum: VACUUM trk.move (to prevent wraparound).
So what is the meaning of "(to prevent wraparound)" here ?
Will it impact the autovacuum anyhow ?
Please help me.
Regards,
Atul
Kind regards,
Jessica Sharp
---------------------
(469) 602-2363
Thanks Jessica. Could help me out by sharing documents that can help me understand “to prevent wraparound “ in simplest way, postgres doc is little bit harder for a newbee like me.
On Thursday, November 26, 2020, Jessica Sharp <jessica@thesharpgeek.com> wrote:
Regards
Atul
On Thursday, November 26, 2020, Jessica Sharp <jessica@thesharpgeek.com> wrote:
Hi Atul,This means autovacuum is doing it’s job — most likely no need to be alarmed here based on this alone. The autovacuum is helping avoid a txid limit. This is part of PostgreSQL MVCC. You may check that section of the documentation for more information on this.--On Wed, Nov 25, 2020 at 22:54 Atul Kumar <akumar14871@gmail.com> wrote:Hi,
I have autovacuum running in background from last 30-40 minutes but I
noticed that it is with "(to prevent wraparound)" say for example
autovacuum: VACUUM trk.move (to prevent wraparound).
So what is the meaning of "(to prevent wraparound)" here ?
Will it impact the autovacuum anyhow ?
Please help me.
Regards,
AtulKind regards,Jessica Sharp---------------------(469) 602-2363
Absolutely. This may be helpful:
On Wed, Nov 25, 2020 at 23:09 Atul Kumar <akumar14871@gmail.com> wrote:
Thanks Jessica. Could help me out by sharing documents that can help me understand “to prevent wraparound “ in simplest way, postgres doc is little bit harder for a newbee like me.RegardsAtul
On Thursday, November 26, 2020, Jessica Sharp <jessica@thesharpgeek.com> wrote:Hi Atul,This means autovacuum is doing it’s job — most likely no need to be alarmed here based on this alone. The autovacuum is helping avoid a txid limit. This is part of PostgreSQL MVCC. You may check that section of the documentation for more information on this.--On Wed, Nov 25, 2020 at 22:54 Atul Kumar <akumar14871@gmail.com> wrote:Hi,
I have autovacuum running in background from last 30-40 minutes but I
noticed that it is with "(to prevent wraparound)" say for example
autovacuum: VACUUM trk.move (to prevent wraparound).
So what is the meaning of "(to prevent wraparound)" here ?
Will it impact the autovacuum anyhow ?
Please help me.
Regards,
AtulKind regards,Jessica Sharp---------------------(469) 602-2363
Kind regards,
Jessica Sharp
---------------------
(469) 602-2363
On Wed, Nov 25, 2020 at 11:10:50PM -0700, Jessica Sharp wrote: > On Wed, Nov 25, 2020 at 23:09 Atul Kumar <akumar14871@gmail.com> wrote: >> Thanks Jessica. Could help me out by sharing documents that can help me >> understand “to prevent wraparound “ in simplest way, postgres doc is little >> bit harder for a newbee like me. > > Absolutely. This may be helpful: > https://youtu.be/bA1SgWn6Gv4 If you have any suggestions on how to improve this part of the docs, please feel free: https://www.postgresql.org/docs/devel/routine-vacuuming.html#VACUUM-FOR-WRAPAROUND Note that due to the critical work that such vacuum jobs do, they cannot be cancelled. -- Michael