Re: Platform-dependent(?) failure in timeout handling - Mailing list pgsql-hackers

From Andres Freund
Subject Re: Platform-dependent(?) failure in timeout handling
Date
Msg-id 20131127090202.GB28863@alap2.anarazel.de
Whole thread Raw
In response to Platform-dependent(?) failure in timeout handling  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Hi,

On 2013-11-26 18:50:28 -0500, Tom Lane wrote:
> I don't know how many platforms block signals during handlers in this way,
> but I'm seeing it on Linux (RHEL6.5 to be exact) and we know that at least
> OpenBSD acts likewise, so that's a pretty darn large chunk of the world.

Just as a datapoint, I think on linux (and likely on any system using
sigaction()) that depends on how you setup the signal handler. There's a
flag that controls that behaviour, namely SA_NODEFER.
When using signal(2) the behaviour depends on the flavor of system we're
running and even on some #defines.

I am not really sure whether using SA_NODEFER would be a good idea, even
if we could achieve that behaviour on all platforms.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
Services



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