Date: Fri, 16 Apr 2021 22:18:37 -0500
From: Justin Pryzby <pryzby@telsasoft.com>
To: Andres Freund <andres@anarazel.de>
Cc: pgsql-hackers@postgresql.org, Tom Lane <tgl@sss.pgh.pa.us>
Subject: Re: terminate called after throwing an instance of 'std::bad_alloc'
Message-ID: <20210417031837.GM3315@telsasoft.com>
References: <20201001021609.GC8476@telsasoft.com>
 <20201003220236.GL8476@telsasoft.com>
 <20201003230149.mtd7fjsjwgii3jv7@alap3.anarazel.de>
 <20201003233045.GM8476@telsasoft.com>
 <20201004020127.zbrol2ypu6tg2bei@alap3.anarazel.de>
 <20201007230242.rnwsbnxywvthef3w@alap3.anarazel.de>
 <20201218235607.GC30237@telsasoft.com>
 <20210417021755.xdcqaqqt4y46wzt7@alap3.anarazel.de>
 <20210417024854.GL3315@telsasoft.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20210417024854.GL3315@telsasoft.com>
User-Agent: Mutt/1.9.4 (2018-02-28)
Archived-At: 
 <https://www.postgresql.org/message-id/20210417031837.GM3315%40telsasoft.com>
Precedence: bulk

On Fri, Apr 16, 2021 at 09:48:54PM -0500, Justin Pryzby wrote:
> On Fri, Apr 16, 2021 at 07:17:55PM -0700, Andres Freund wrote:
> > Hi,
> > 
> > On 2020-12-18 17:56:07 -0600, Justin Pryzby wrote:
> > > I'd be happy to run with a prototype fix for the leak to see if the other issue
> > > does (not) recur.
> > 
> > I just posted a prototype fix to https://www.postgresql.org/message-id/20210417021602.7dilihkdc7oblrf7%40alap3.anarazel.de
> > (just because that was the first thread I re-found). It'd be cool if you
> > could have a look!
> 
> This doesn't seem to address the problem triggered by the reproducer at
> https://www.postgresql.org/message-id/20210331040751.GU4431@telsasoft.com
> (sorry I didn't CC you)

I take that back - I forgot that this doesn't release RAM until hitting a
threshold.

Without the patch, it looks like:

$ yes 'SET jit_above_cost=0; SET jit_inline_above_cost=0; SET jit=on; SET client_min_messages=debug; SET log_executor_stats=on; SELECT cfn();' |head -11 |psql -h /tmp postgres 2>&1 |grep 'max resident'
!       61820 kB max resident size
!       65020 kB max resident size
!       68812 kB max resident size
!       71152 kB max resident size
!       76820 kB max resident size
!       78760 kB max resident size
!       81140 kB max resident size
!       83520 kB max resident size
!       93084 kB max resident size
!       94756 kB max resident size
!       96416 kB max resident size

With the patch and #define LLVMJIT_LLVM_CONTEXT_REUSE_MAX 1, it looks like
this:

!       61436 kB max resident size
!       61572 kB max resident size
!       63236 kB max resident size
!       63236 kB max resident size
!       63556 kB max resident size
!       63556 kB max resident size
!       63880 kB max resident size
!       65416 kB max resident size
!       65416 kB max resident size
!       65416 kB max resident size
!       65416 kB max resident size

-- 
Justin