daemon: set TCP_DEFER_ACCEPT on everything but NNTP

[public-inbox.git] / lib / PublicInbox / Daemon.pm

diff --git a/lib/PublicInbox/Daemon.pm b/lib/PublicInbox/Daemon.pm
index c4481555d43e66a7065b21e39bce4648a5780c85..8b59b65fc13f7cde1e624b4a3582e0041e13fb2d 100644 (file)
--- a/lib/PublicInbox/Daemon.pm
+++ b/lib/PublicInbox/Daemon.pm
@@ -8,6 +8,7 @@ use warnings;
 use Getopt::Long qw/:config gnu_getopt no_ignore_case auto_abbrev/;
 use IO::Handle;
 use IO::Socket;
+use Socket qw(IPPROTO_TCP);
 use Cwd qw/abs_path/;
 STDOUT->autoflush(1);
 STDERR->autoflush(1);
@@ -552,6 +553,18 @@ sub tls_start_cb ($$) {
        }
 }
 
+sub defer_accept ($) {
+       if ($^O eq 'linux') {
+               my ($s) = @_;
+               my $x = getsockopt($s, IPPROTO_TCP, Socket::TCP_DEFER_ACCEPT());
+               return unless defined $x; # may be Unix socket
+               my $sec = unpack('i', $x);
+               return if $sec > 0; # systemd users may set a higher value
+               setsockopt($s, IPPROTO_TCP, Socket::TCP_DEFER_ACCEPT(), 1);
+       }
+       # TODO FreeBSD accf_http / accf_data
+}
+
 sub daemon_loop ($$$) {
        my ($refresh, $post_accept, $nntpd) = @_;
        PublicInbox::EvCleanup::enable(); # early for $refresh
@@ -581,10 +594,15 @@ sub daemon_loop ($$$) {
        $SIG{HUP} = $refresh;
        $SIG{CHLD} = 'DEFAULT';
        $SIG{$_} = 'IGNORE' for qw(USR2 TTIN TTOU WINCH);
-       # this calls epoll_create:
-       @listeners = map {
-               PublicInbox::Listener->new($_,
-                               $post_accept{sockname($_)} || $post_accept)
+       @listeners = map {;
+               my $tls_cb = $post_accept{sockname($_)};
+
+               # NNTPS, HTTPS, HTTP, and POP3S are client-first traffic
+               # NNTP and POP3 are server-first
+               defer_accept($_) if $tls_cb || !$nntpd;
+
+               # this calls epoll_create:
+               PublicInbox::Listener->new($_, $tls_cb || $post_accept)
        } @listeners;
        PublicInbox::DS->EventLoop;
        $parent_pipe = undef;