From: Alex Balashov <abalashov@evaristesys.com>
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Subject: Re: Unexplained rapid growth in memory usage of idle backends
Date: Sat, 13 May 2023 19:49:58 -0400
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To: Tom Lane <tgl@sss.pgh.pa.us>,
 pgsql-admin <pgsql-admin@lists.postgresql.org>
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> On May 12, 2023, at 9:52 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>=20
> Alex Balashov <abalashov@evaristesys.com> writes:
>> Occasionally, about once every 2 months, we'll get a slow-motion =
implosion over a period of about 24 hours, where the resident memory =
size of some of the backends shoots up from a reasonable few hundred MB =
to several gigs -- and will keep growing, e.g.
>=20
> I'm a little suspicious that the excess memory consumption is a
> consequence of JIT-compiled code not getting recycled promptly.
> Do you have JIT enabled, and if so are you relying on it too much
> to turn it off?
>=20
> I don't have any concrete idea of why JIT code management would work
> fine and then stop working fine, but we do have other reports of
> memory leaks from that.

Hi Tom, thanks for your response. JIT is enabled, but I'm not familiar =
with this feature and not sure what we are using which would touch JIT =
somehow.=20

Also, am I wrong to imagine that a memory leak would leak memory =
gradually over time, rather than to be set off at some arbitrary point =
by the same exact workload that has been visited upon the database for =
the previous 1-2 months hitherto?

-- Alex

--=20
Alex Balashov
Principal Consultant
Evariste Systems LLC
Web: https://evaristesys.com
Tel: +1-706-510-6800