From: Tom Lane <tgl@sss.pgh.pa.us>
To: Tomas Vondra <tv@fuzzy.cz>
Cc: Andres Freund <andres@anarazel.de>
Cc: Simon Riggs <simon@2ndquadrant.com>
Cc: pgsql-committers <pgsql-committers@postgresql.org>
Subject: Re: pgsql: Generational memory allocator
Date: Sat, 25 Nov 2017 14:50:41 -0500
Message-ID: <8991.1511639441@sss.pgh.pa.us> (raw)
In-Reply-To: <6189.1511587105@sss.pgh.pa.us>
References: <E1eHa4J-0006hI-Q8@gemulon.postgresql.org>
<20171123001649.y2nf7422iay6cw3v@alap3.anarazel.de>
<CANP8+jKoT=Pg5W_3FcKiDf+FMrJhFYacxt_g5E0=tkmb5s8M6g@mail.gmail.com>
<c903f275-2150-fa52-64bf-dca7b53ebf8d@fuzzy.cz>
<16449.1511548313@sss.pgh.pa.us>
<4618.1511573138@sss.pgh.pa.us>
<bf84d940-90d4-de91-19dd-612e011007f4@fuzzy.cz>
<6189.1511587105@sss.pgh.pa.us>
I wrote:
> Tomas Vondra <tv@fuzzy.cz> writes:
>> BTW I also see these failures in hstore:
>> ==15168== Source and destination overlap in memcpy(0x5d0fed0, 0x5d0fed0, 40)
>> ==15168== at 0x4C2E00C: memcpy@@GLIBC_2.14 (vg_replace_strmem.c:1018)
>> ==15168== by 0x15419A06: hstoreUniquePairs (hstore_io.c:343)
>> ==15168== by 0x15419EE4: hstore_in (hstore_io.c:416)
> Huh ...
I tried to duplicate this on my RHEL6 workstation, and failed to,
even though adding an assertion easily proves that the hstore
regression test does exercise the case. So apparently the answer
as to why skink isn't reporting this is just "not all versions of
valgrind check it".
I checked the git history and noted that we've previously fixed other
nominally-undefined usage of memcpy() on the grounds that OpenBSD's
libc will complain about it. So it seems like something that would
be good to fix, and I did so.
Meanwhile, skink has come back with a success as of 0f2458f, rendering
the other mystery even deeper --- although at least this confirms the
idea that the crashes we are seeing predate the generation.c patch.
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-committers@postgresql.org
Cc: tgl@sss.pgh.pa.us, tv@fuzzy.cz, andres@anarazel.de, simon@2ndquadrant.com
Subject: Re: pgsql: Generational memory allocator
In-Reply-To: <8991.1511639441@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