From: Tom Lane <tgl@sss.pgh.pa.us>
To: frank picabia <fpicabia@gmail.com>
Cc: pgsql-admin@postgresql.org
Subject: Re: Error: "could not fork new process for connection: Cannot allocate memory"
Date: Mon, 21 Dec 2020 20:27:43 -0500
Message-ID: <574264.1608600463@sss.pgh.pa.us> (raw)
In-Reply-To: <CA+AKB6HxKgOvKAL8yuH7=Sc9ENs5Me4ouoGR16e9H3EdCWvKqg@mail.gmail.com>
References: <CA+AKB6F6EGnLPFDqm1kcPtyeRWyY92vbfQk-3uFVbrERYu+PJg@mail.gmail.com>
<fce391ac5b00b86921e680ebd37eaa802e51dd39.camel@cybertec.at>
<492638.1608564438@sss.pgh.pa.us>
<CA+AKB6FUXcJH32YX9UYgV749NqBFMOh270moE7izBcZt+-VyJg@mail.gmail.com>
<CA+AKB6HxKgOvKAL8yuH7=Sc9ENs5Me4ouoGR16e9H3EdCWvKqg@mail.gmail.com>
frank picabia <fpicabia@gmail.com> writes:
> My VMware admin has come back with a graph showing memory use over
> the period in question. He has looked over other indicators
> and there are no alarms triggered on the system.
> It jives with what Cacti reported. Memory was never exhausted
> and used only 50% of allocated RAM at the most.
> If it's not a configuration issue in Postgres, and both internal and
> external tools
> show memory was not consumed to the point of firing off the "cannot fork"
> error, would that mean that there is a bug in either the kernel or Postgres?
[ shrug... ] Postgres is just reporting to you that the kernel wouldn't
perform a fork(). Since you've gone to great lengths to show that
Postgres isn't consuming excessive resources, either this is a kernel bug
or you're running into some kernel-level (not Postgres) allocation limit.
I continue to suspect the latter. Desultory googling shows that VMware
can be configured to enforce resource allocation limits, so maybe you
should be taking a hard look at your VMware settings.
regards, tom lane
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-admin@postgresql.org
Cc: tgl@sss.pgh.pa.us, fpicabia@gmail.com
Subject: Re: Error: "could not fork new process for connection: Cannot allocate memory"
In-Reply-To: <574264.1608600463@sss.pgh.pa.us>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox