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From: Nathan Bossart <nathandbossart@gmail.com>
To: Sami Imseih <samimseih@gmail.com>
Cc: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Robert Haas <robertmhaas@gmail.com>
Cc: pgsql-hackers@postgresql.org <pgsql-hackers@postgresql.org>
Subject: Re: Restart pg_usleep when interrupted
Date: Thu, 11 Jul 2024 10:34:06 -0500
Message-ID: <Zo_7blmO166ZDGbW@nathan> (raw)
In-Reply-To: <C18017A1-EDFD-4F2F-BCA1-0572D4CCC92B@gmail.com>
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+		/*
+		 * We allow nanosleep to handle interrupts and retry with the remaining time.
+		 * However, since nanosleep is susceptible to time drift when interrupted
+		 * frequently, we add a safeguard to break out of the nanosleep whenever the
+		 * total time of the sleep exceeds the requested sleep time. Using nanosleep
+		 * is a more portable approach than clock_nanosleep.
+		 */

I'm curious why we wouldn't just subtract "elapsed_time" from "delay" at
the bottom of the while loop to avoid needing this extra check.  Also, I
think we need some commentary about why we want to retry after an interrupt
in this case.

-- 
nathan

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  Cc: nathandbossart@gmail.com, samimseih@gmail.com, bertranddrouvot.pg@gmail.com, tgl@sss.pgh.pa.us, robertmhaas@gmail.com
  Subject: Re: Restart pg_usleep when interrupted
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