daemon: set TCP_DEFER_ACCEPT on everything but NNTP

This Linux-specific option can save us some wakeups during
the TLS negotiation phase, and it can help with ordinary HTTP,
too.

Plain NNTP (and in the future, POP3) are the only things which
require the server send messages, first.

1 files changed, 8 insertions, 0 deletions

diff --git a/t/httpd.t b/t/httpd.t
index c061031c..8c2a3173 100644
--- a/t/httpd.t
+++ b/t/httpd.t
@@ -10,6 +10,7 @@ foreach my $mod (qw(Plack::Util Plack::Builder HTTP::Date HTTP::Status)) {
 }
 use File::Temp qw/tempdir/;
 use IO::Socket::INET;
+use Socket qw(IPPROTO_TCP);
 require './t/common.perl';
 
 # FIXME: too much setup
@@ -99,6 +100,13 @@ EOF
                 'fsck on cloned directory successful');
 }
 
+SKIP: {
+        skip 'TCP_DEFER_ACCEPT is Linux-only', 1 if $^O ne 'linux';
+        my $var = Socket::TCP_DEFER_ACCEPT();
+        defined(my $x = getsockopt($sock, IPPROTO_TCP, $var)) or die;
+        ok(unpack('i', $x) > 0, 'TCP_DEFER_ACCEPT set');
+};
+
 done_testing();
 
 1;