Re: PgSQL 12 on WinSrv ~3x faster than on Linux

On Fri, 4 Jun 2021 at 23:53, Taras Savchuk <taras(at)1adm(dot)ru> wrote:
> My real life test is to "register" 10 _same_ documents (провести документы) in each of 1C/PostgreSQL DBs. Both PostgreSQL DBs are identical and just before test imported to PostgreSQL via application server (DT import).
> On Windows Server test procedure takes 20-30 seconds, on Linux it takes 1m-1m10seconds. PostgreSQL VMs are running on same Hypervisor with same resources assigned to each of them.
> Tuning PostgreSQL config and/or CentOS don't make any difference. Contrary on Windows VM we have almost 3x better performance with stock PostgreSQL config.
>
> Any ideas what's wrong? For me such a big difference on identical databases/queries looks strange.

It's pretty difficult to say. You've not provided any useful details
about the workload you're running.

If this "register 10 _same_ documents" thing requires running some
query, then you might want to look at EXPLAIN (ANALYZE, BUFFERS) for
that query. You might want to consider doing SET track_io_timing =
on; Perhaps Linux is having to read more buffers from disk than
Windows.

David.