From 9427c808130255911dd3e4eee99b6f2c1cc42066 Mon Sep 17 00:00:00 2001
From: Eric Wong <e@80x24.org>
Date: Sat, 5 Jan 2019 21:52:57 +0000
Subject: shrink low-bandwidth pipes under Linux

I've hit /proc/sys/fs/pipe-user-pages-* limits on some systems.
So stop hogging resources on pipes which don't benefit from
giant sizes.

Some of these can use eventfd in the future to further reduce
resource use.
---
 lib/PublicInbox/Git.pm | 4 ++++
 1 file changed, 4 insertions(+)

(limited to 'lib/PublicInbox/Git.pm')

diff --git a/lib/PublicInbox/Git.pm b/lib/PublicInbox/Git.pm
index 95df52ed..16117277 100644
--- a/lib/PublicInbox/Git.pm
+++ b/lib/PublicInbox/Git.pm
@@ -37,6 +37,10 @@ sub _bidi_pipe {
 
 	pipe($in_r, $in_w) or fail($self, "pipe failed: $!");
 	pipe($out_r, $out_w) or fail($self, "pipe failed: $!");
+	if ($^O eq 'linux') { # 1031: F_SETPIPE_SZ
+		fcntl($out_w, 1031, 4096);
+		fcntl($in_w, 1031, 4096) if $batch eq '--batch-check';
+	}
 
 	my @cmd = ('git', "--git-dir=$self->{git_dir}", qw(cat-file), $batch);
 	my $redir = { 0 => fileno($out_r), 1 => fileno($in_w) };
-- 
cgit v1.2.3-24-ge0c7