Date: Tue, 13 Aug 2024 10:57:24 -0500
From: Nathan Bossart <nathandbossart@gmail.com>
To: "Imseih (AWS), Sami" <samimseih@gmail.com>
Cc: Heikki Linnakangas <hlinnaka@iki.fi>,
	Bertrand Drouvot <bertranddrouvot.pg@gmail.com>,
	Tom Lane <tgl@sss.pgh.pa.us>, Robert Haas <robertmhaas@gmail.com>,
	"pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Subject: Re: Restart pg_usleep when interrupted
Message-ID: <ZruCZOKzS0LGAGTb@nathan>
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On Tue, Aug 13, 2024 at 10:47:51AM -0500, Imseih (AWS), Sami wrote:
> On 8/13/24 10:09 AM, Nathan Bossart wrote:
>> On Mon, Aug 12, 2024 at 05:35:08PM -0500, Imseih (AWS), Sami wrote:
>> > > Skimming the last few messages of that thread [0], it looks like Bertrand
>> > > is exploring ways to avoid so many interrupts.  I guess the unavoidable
>> > > question is whether this work is still worthwhile given that improvement.
>> > The way the instrumentation in [0] dealt with interrupts was too complex,
>> > which is why it seemed better to handle the restart the remainder of the
>> > sleep in the sleep function
>> Can you elaborate on how it is too complex?
>> 
> [0] made vacuum_delay_point more complex as it has to
> instrument cost_delay at an interval to reduce the number
> of interrupts to the leader.

Sure, but looking at the patch [0], it adds maybe an extra 10 lines of code
to limit the reports to 1 Hz.  That doesn't strike me as too complex...

[0] https://postgr.es/m/ZnlPZZZJCRu/8fka%40ip-10-97-1-34.eu-west-3.compute.internal

-- 
nathan