Re: [HACKERS] Slow synchronous logical replication

2017-10-12 Thread Craig Ringer
On 12 October 2017 at 16:09, Konstantin Knizhnik wrote: > > Is the CREATE TABLE and INSERT done in the same transaction? > > No. Table was create in separate transaction. > Moreover the same effect will take place if table is create before start of > replication. > The problem in this case seem

Re: [HACKERS] Slow synchronous logical replication

2017-10-12 Thread Konstantin Knizhnik
On 12.10.2017 04:23, Craig Ringer wrote: On 12 October 2017 at 00:57, Konstantin Knizhnik wrote: The reason of such behavior is obvious: wal sender has to decode huge transaction generate by insert although it has no relation to this publication. It does. Though I wouldn't expect anywhere n

Re: [HACKERS] Slow synchronous logical replication

2017-10-11 Thread Craig Ringer
On 12 October 2017 at 00:57, Konstantin Knizhnik wrote: > The reason of such behavior is obvious: wal sender has to decode huge > transaction generate by insert although it has no relation to this > publication. It does. Though I wouldn't expect anywhere near the kind of drop you report, and hav

Re: [HACKERS] Slow synchronous logical replication

2017-10-11 Thread Konstantin Knizhnik
On 11.10.2017 10:07, Craig Ringer wrote: On 9 October 2017 at 15:37, Konstantin Knizhnik wrote: Thank you for explanations. On 08.10.2017 16:00, Craig Ringer wrote: I think it'd be helpful if you provided reproduction instructions, test programs, etc, making it very clear when things are /

Re: [HACKERS] Slow synchronous logical replication

2017-10-11 Thread Andres Freund
Hi, On 2017-10-09 10:37:01 +0300, Konstantin Knizhnik wrote: > So we have implement sharding - splitting data between several remote tables > using pg_pathman and postgres_fdw. > It means that insert or update of parent table cause insert or update of > some derived partitions which is forwarded

Re: [HACKERS] Slow synchronous logical replication

2017-10-11 Thread Craig Ringer
On 9 October 2017 at 15:37, Konstantin Knizhnik wrote: > Thank you for explanations. > > On 08.10.2017 16:00, Craig Ringer wrote: >> >> I think it'd be helpful if you provided reproduction instructions, >> test programs, etc, making it very clear when things are / aren't >> related to your changes

Re: [HACKERS] Slow synchronous logical replication

2017-10-10 Thread Masahiko Sawada
On Mon, Oct 9, 2017 at 4:37 PM, Konstantin Knizhnik wrote: > Thank you for explanations. > > On 08.10.2017 16:00, Craig Ringer wrote: >> >> I think it'd be helpful if you provided reproduction instructions, >> test programs, etc, making it very clear when things are / aren't >> related to your cha

Re: [HACKERS] Slow synchronous logical replication

2017-10-09 Thread Konstantin Knizhnik
Thank you for explanations. On 08.10.2017 16:00, Craig Ringer wrote: I think it'd be helpful if you provided reproduction instructions, test programs, etc, making it very clear when things are / aren't related to your changes. It will be not so easy to provide some reproducing scenario, becaus

Re: [HACKERS] Slow synchronous logical replication

2017-10-08 Thread Craig Ringer
On 8 October 2017 at 03:58, Konstantin Knizhnik wrote: > The question was about logical replication mechanism in mainstream version > of Postgres. I think it'd be helpful if you provided reproduction instructions, test programs, etc, making it very clear when things are / aren't related to your

Re: [HACKERS] Slow synchronous logical replication

2017-10-07 Thread Konstantin Knizhnik
On 10/07/2017 10:42 PM, Andres Freund wrote: Hi, On 2017-10-07 22:39:09 +0300, konstantin knizhnik wrote: In our sharded cluster project we are trying to use logical relication for providing HA (maintaining redundant shard copies). Using asynchronous logical replication has not so much sense i

Re: [HACKERS] Slow synchronous logical replication

2017-10-07 Thread Andres Freund
Hi, On 2017-10-07 22:39:09 +0300, konstantin knizhnik wrote: > In our sharded cluster project we are trying to use logical relication for > providing HA (maintaining redundant shard copies). > Using asynchronous logical replication has not so much sense in context of > HA. This is why we try to