X-Git-Url: http://www.git.stargrave.org/?a=blobdiff_plain;f=lib%2FPublicInbox%2FV2Writable.pm;h=fc2f33f9dd2cd09f48b89cc5d2629ae2f1e6f3b7;hb=95bdac7f09c69036efed537a4d03d5bdd2ae4eb6;hp=9073d9ef89a8db95dd3db2d7c1b76cc26b758194;hpb=c5c709dcef1b5904467ff2aea3943f00a891dade;p=public-inbox.git

diff --git a/lib/PublicInbox/V2Writable.pm b/lib/PublicInbox/V2Writable.pm
index 9073d9ef..fc2f33f9 100644
--- a/lib/PublicInbox/V2Writable.pm
+++ b/lib/PublicInbox/V2Writable.pm
@@ -1,4 +1,4 @@
-# Copyright (C) 2018-2019 all contributors <meta@public-inbox.org>
+# Copyright (C) 2018-2020 all contributors <meta@public-inbox.org>
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
 
 # This interface wraps and mimics PublicInbox::Import
@@ -7,6 +7,7 @@ package PublicInbox::V2Writable;
 use strict;
 use warnings;
 use base qw(PublicInbox::Lock);
+use 5.010_001;
 use PublicInbox::SearchIdxShard;
 use PublicInbox::MIME;
 use PublicInbox::Git;
@@ -32,19 +33,29 @@ my $PACKING_FACTOR = 0.4;
 # to increase Xapian shards
 our $NPROC_MAX_DEFAULT = 4;
 
-sub nproc_shards ($) {
-	my ($creat_opt) = @_;
-	if (ref($creat_opt) eq 'HASH') {
-		if (defined(my $n = $creat_opt->{nproc})) {
-			return $n
-		}
+sub detect_nproc () {
+	for my $nproc (qw(nproc gnproc)) { # GNU coreutils nproc
+		`$nproc 2>/dev/null` =~ /^(\d+)$/ and return $1;
+	}
+
+	# getconf(1) is POSIX, but *NPROCESSORS* vars are not
+	for (qw(_NPROCESSORS_ONLN NPROCESSORS_ONLN)) {
+		`getconf $_ 2>/dev/null` =~ /^(\d+)$/ and return $1;
 	}
 
-	my $n = $ENV{NPROC};
+	# should we bother with `sysctl hw.ncpu`?  Those only give
+	# us total processor count, not online processor count.
+	undef
+}
+
+sub nproc_shards ($) {
+	my ($creat_opt) = @_;
+	my $n = $creat_opt->{nproc} if ref($creat_opt) eq 'HASH';
+	$n //= $ENV{NPROC};
 	if (!$n) {
-		chomp($n = `nproc 2>/dev/null`);
-		# assume 2 cores if GNU nproc(1) is not available
-		$n = 2 if !$n;
+		# assume 2 cores if not detectable or zero
+		state $NPROC_DETECTED = detect_nproc() || 2;
+		$n = $NPROC_DETECTED;
 		$n = $NPROC_MAX_DEFAULT if $n > $NPROC_MAX_DEFAULT;
 	}
 
@@ -112,8 +123,11 @@ sub new {
 
 # public (for now?)
 sub init_inbox {
-	my ($self, $parallel, $skip_epoch) = @_;
-	$self->{parallel} = $parallel;
+	my ($self, $shards, $skip_epoch) = @_;
+	if (defined $shards) {
+		$self->{parallel} = 0 if $shards == 0;
+		$self->{shards} = $shards if $shards > 0;
+	}
 	$self->idx_init;
 	my $epoch_max = -1;
 	git_dir_latest($self, \$epoch_max);
@@ -663,23 +677,43 @@ sub fill_alternates ($$) {
 	unless (-d $all) {
 		PublicInbox::Import::init_bare($all);
 	}
-	my $alt = "$all/objects/info/alternates";
-	my %alts;
-	my @add;
+	my $info_dir = "$all/objects/info";
+	my $alt = "$info_dir/alternates";
+	my (%alt, $new);
+	my $mode = 0644;
 	if (-e $alt) {
 		open(my $fh, '<', $alt) or die "open < $alt: $!\n";
-		%alts = map { chomp; $_ => 1 } (<$fh>);
+		$mode = (stat($fh))[2] & 07777;
+
+		# we assign a sort score to every alternate and favor
+		# the newest (highest numbered) one when we
+		my $score;
+		my $other = 0; # in case admin adds non-epoch repos
+		%alt = map {;
+			if (m!\A\Q../../\E([0-9]+)\.git/objects\z!) {
+				$score = $1 + 0;
+			} else {
+				$score = --$other;
+			}
+			$_ => $score;
+		} split(/\n+/, do { local $/; <$fh> });
 	}
+
 	foreach my $i (0..$epoch) {
 		my $dir = "../../git/$i.git/objects";
-		push @add, $dir if !$alts{$dir} && -d "$pfx/$i.git";
-	}
-	return unless @add;
-	open my $fh, '>>', $alt or die "open >> $alt: $!\n";
-	foreach my $dir (@add) {
-		print $fh "$dir\n" or die "print >> $alt: $!\n";
+		if (!exists($alt{$dir}) && -d "$pfx/$i.git") {
+			$alt{$dir} = $i;
+			$new = 1;
+		}
 	}
-	close $fh or die "close $alt: $!\n";
+	return unless $new;
+
+	my ($fh, $tmp) = tempfile('alt-XXXXXXXX', DIR => $info_dir);
+	print $fh join("\n", sort { $alt{$b} <=> $alt{$a} } keys %alt), "\n"
+		or die "print $tmp: $!\n";
+	chmod($mode, $fh) or die "fchmod $tmp: $!\n";
+	close $fh or die "close $tmp $!\n";
+	rename($tmp, $alt) or die "rename $tmp => $alt: $!\n";
 }
 
 sub git_init {