Date: Thu, 11 Jul 2024 10:34:06 -0500
From: Nathan Bossart <nathandbossart@gmail.com>
To: Sami Imseih <samimseih@gmail.com>
Cc: 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: <Zo_7blmO166ZDGbW@nathan>
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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