Re: [GENERAL] Question regarding logical replication

2017-10-27 Thread Weiping Qu
Thanks, Francisco. From the plots we got the same feeling, cache reads with little lags and high cache hits really don't put extra burden on the original write throughput for OLTP transactions. And log-based is the most efficient and harm-less one as compared to trigger-based and timestamp

Re: [GENERAL] Question regarding logical replication

2017-10-27 Thread Francisco Olarte
On Fri, Oct 27, 2017 at 12:04 PM, Weiping Qu wrote: > That's a good point and we haven't accounted for disk caching. > Is there any way to confirm this fact in PostgreSQL? I doubt, as it names indicates cache should be hidden from the db server. You could monitor the

Re: [GENERAL] Question regarding logical replication

2017-10-27 Thread Weiping Qu
That's a good point and we haven't accounted for disk caching. Is there any way to confirm this fact in PostgreSQL? Weiping On 27.10.2017 11:53, Francisco Olarte wrote: On Thu, Oct 26, 2017 at 10:20 PM, Weiping Qu wrote: However, the plots showed different trend

Re: [GENERAL] Question regarding logical replication

2017-10-27 Thread Francisco Olarte
On Thu, Oct 26, 2017 at 10:20 PM, Weiping Qu wrote: > However, the plots showed different trend (currently I don't have plots on > my laptop) which shows that the more frequently are the CDC processes > reading from logical slots, the less overhead is incurred over

Re: [GENERAL] Question regarding logical replication

2017-10-26 Thread Weiping Qu
;PostgreSql-general" <pgsql-general@postgresql.org> Sent: Thursday, 26 October, 2017 14:07:54 Subject: [GENERAL] Question regarding logical replication Dear postgresql community, I have a question regarding understanding the implementation logic behind logical replication. Assume a replicat

Re: [GENERAL] Question regarding logical replication

2017-10-26 Thread Alvaro Aguayo Garcia-Rada
Sent: Thursday, 26 October, 2017 14:07:54 Subject: [GENERAL] Question regarding logical replication Dear postgresql community, I have a question regarding understanding the implementation logic behind logical replication. Assume a replication slot created on the master node, will more and

[GENERAL] Question regarding logical replication

2017-10-26 Thread Weiping Qu
Dear postgresql community, I have a question regarding understanding the implementation logic behind logical replication. Assume a replication slot created on the master node, will more and more data get piled up in the slot and the size of replication slot continuously increase if there is