From: Eric Wong <e@80x24.org>
Date: Mon, 18 Sep 2023 10:15:10 +0000 (+0000)
Subject: drop GNU nproc(1) support in favor of getconf(1)
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6b70d5f03b688ee24df38ea669c0d800a6ad3b49;p=thirdparty%2Fpublic-inbox.git

drop GNU nproc(1) support in favor of getconf(1)

`getconf NPROCESSORS_ONLN' will succeed on GNU/Linux systems
anyways; and the non-underscore-prefixed invocation works fine
on all BSD flavors tested.

Thus the `nproc' and `gnproc' attempts will never be reached.
The only downside is we lose the ability to account for CPU
affinity, but that's probably not an issue since CPU affinity
(AFAIK) isn't a commonly-used feature.
---

diff --git a/Makefile.PL b/Makefile.PL
index 5b7914dc5..97e00395e 100644
--- a/Makefile.PL
+++ b/Makefile.PL
@@ -199,8 +199,8 @@ WriteMakefile(
 );
 
 sub MY::postamble {
-	my $N = (`{ getconf _NPROCESSORS_ONLN || getconf NPROCESSORS_ONLN ||
-		gnproc || nproc; } 2>/dev/null` || 1);
+	my $N = (`{ getconf _NPROCESSORS_ONLN ||
+		getconf NPROCESSORS_ONLN; } 2>/dev/null` || 1);
 	$N += 1; # account for sleeps in some tests (and makes an IV)
 	<<EOF;
 PROVE = prove
diff --git a/ci/run.sh b/ci/run.sh
index 93790269f..bd1d8a4d6 100755
--- a/ci/run.sh
+++ b/ci/run.sh
@@ -12,7 +12,7 @@ then
 	$DO $MAKE clean >/dev/null
 fi
 NPROC=${NPROC-$({ getconf _NPROCESSORS_ONLN || getconf NPROCESSORS_ONLN ||
-	gnproc || nproc || echo 2; } 2>/dev/null)}
+		echo 2; } 2>/dev/null)}
 
 TEST_JOBS=${TEST_JOBS-1}
 $PERL -w ci/profiles.perl | while read args
diff --git a/lib/PublicInbox/IPC.pm b/lib/PublicInbox/IPC.pm
index 39021f425..fa0847950 100644
--- a/lib/PublicInbox/IPC.pm
+++ b/lib/PublicInbox/IPC.pm
@@ -464,16 +464,13 @@ sub detect_nproc () {
 	my $n = $NPROCESSORS_ONLN{$^O};
 	return POSIX::sysconf($n) if defined $n;
 
-	# getconf(1) is POSIX, but *NPROCESSORS* vars are not
+	# getconf(1) is POSIX, but *NPROCESSORS* vars are not even if
+	# glibc, {Free,Net,Open}BSD all support them.
 	for (qw(_NPROCESSORS_ONLN NPROCESSORS_ONLN)) {
 		`getconf $_ 2>/dev/null` =~ /^(\d+)$/ and return $1;
 	}
-	for my $nproc (qw(nproc gnproc)) { # GNU coreutils nproc
-		`$nproc 2>/dev/null` =~ /^(\d+)$/ and return $1;
-	}
-
-	# should we bother with `sysctl hw.ncpu`?  Those only give
-	# us total processor count, not online processor count.
+	# note: GNU nproc(1) checks CPU affinity, which is nice but
+	# isn't remotely portable
 	undef
 }