Re: [HACKERS] Server crash due to SIGBUS(Bus Error) when trying toaccess the memory created using dsm_create(). - Mailing list pgsql-hackers

From Thomas Munro
Subject Re: [HACKERS] Server crash due to SIGBUS(Bus Error) when trying toaccess the memory created using dsm_create().
Date
Msg-id CAEepm=37ptJz+epr6+iW+O1wCCAxeT04r27Uc8rXmJBoFT2ExA@mail.gmail.com
Whole thread Raw
In response to Re: [HACKERS] Server crash due to SIGBUS(Bus Error) when trying toaccess the memory created using dsm_create().  (Thomas Munro <thomas.munro@enterprisedb.com>)
Responses Re: [HACKERS] Server crash due to SIGBUS(Bus Error) when trying toaccess the memory created using dsm_create().  (Thomas Munro <thomas.munro@enterprisedb.com>)
List pgsql-hackers
On Thu, Jun 29, 2017 at 12:24 PM, Thomas Munro
<thomas.munro@enterprisedb.com> wrote:
> fallocate-v5.patch

Added to commitfest so we don't lose track of this.

I'm mainly concerned about the fact that we have a way for PostgreSQL
to die that looks exactly like a bug, when really it's masking an
out-of-memory condition that a DBA or sysadmin would normally be able
to diagnose by the appearance of the OOM reaper at the window holding
a scythe.  I suppose the SIGBUS case is much more likely to happen
when we start actively using large amounts of dynamic shared memory
(parallel hash), but I suppose it could happen now if your system is
already overcommitted and a small DSM segment happens to push you over
the edge.

-- 
Thomas Munro
http://www.enterprisedb.com



pgsql-hackers by date:

Previous
From: Michael Paquier
Date:
Subject: Re: [HACKERS] Function to move the position of a replication slot
Next
From: Michael Paquier
Date:
Subject: Re: [HACKERS] [BUGS] Replication to Postgres 10 on Windows is broken