Hello
I have a publisher instance, cpu 32
core, ram 64GB, with SSD and installed PostgreSQL 10 on it. I want to
use logical replication with it , I create publication on it, add
about 20 tables in the pub, each tables will have about 1 million line
data,.
I wonder how many subscriber instance the publisher can affort, what if i have 100 sub,
which
means there will be 100 logical replication slot and 100 wal sender
process on the publisher instance, will so many sub slow down the
publisher performance?
I have test on my own
machine cpu 8core, ram 16GB as a publisher with 10 sub (anthoer machine
start 10 postgres instance, every one create a sub), and everything
works fine. I test pgbench on my 8core, 16GB machine, without sub or
with 10 sub, the tps is the same. Even if there is one million line data
on the pub, and on sub side the table is empty, and when i create
subscription on the 10 postgres sub instance, it copy data from pub is
quickly enough.
I wonder how many logical replication slot or wal sender is ok for the 32core, 64GB machine. 100 sub？ 500 sub?
