From: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
To: Tomas Vondra <tomas.vondra@2ndquadrant.com>
To: pgsql-hackers@lists.postgresql.org
Subject: Re: memory leak when serializing TRUNCATE in reorderbuffer
Date: Wed, 8 Aug 2018 21:19:16 +0200
Message-ID: <04cfcf19-1a43-5d85-918d-56a8620377c4@2ndquadrant.com> (raw)
In-Reply-To: <66175a41-9342-2845-652f-1bd4c3ee50aa@2ndquadrant.com>
References: <66175a41-9342-2845-652f-1bd4c3ee50aa@2ndquadrant.com>
On 20/06/2018 21:42, Tomas Vondra wrote:
> So I think we should fix and serialize/restore the OID array, just like
> we do for tuples, snapshots etc. See the attached fix.
Yes please.
> Another thing we should probably reconsider is where the relids is
> allocated - the pointer remains valid because we happen to allocate it
> in TopMemoryContext. It's not that bad because we don't free the other
> reorderbuffer contexts until the walsender exits anyway, but still.
>
> So I propose to allocate it in rb->context just like the other bits of
> data (snapshots, ...). Replacing the palloc() in DecodeTruncate() with
> something like:
>
> MemoryContextAlloc(ctx->reorder->context,
> xlrec->nrelids * sizeof(Oid));
>
> should do the trick.
It's not clear from the code comments which context would be the
appropriate one.
More standard coding style would be to set the current memory context
somewhere, but I suppose the reorderbuffer.c code isn't written that way.
--
Peter Eisentraut http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
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To: pgsql-hackers@postgresql.org
Cc: peter.eisentraut@2ndquadrant.com, tomas.vondra@2ndquadrant.com, pgsql-hackers@lists.postgresql.org
Subject: Re: memory leak when serializing TRUNCATE in reorderbuffer
In-Reply-To: <04cfcf19-1a43-5d85-918d-56a8620377c4@2ndquadrant.com>
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