From: bluhm <bluhm@openbsd.org>
Date: Sun, 14 Jan 2018 00:53:11 +0000 (+0000)
Subject: Unlocking the TCP stack resulted in smaller TCP segments sent out
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=4f38abc25edad4a17bdca009c30daca81ae35c32;p=openbsd

Unlocking the TCP stack resulted in smaller TCP segments sent out
early on some machines.  Use the TCP_NOPUSH socket option to get
reliable regress results and syslogd(8) debug messages for grep.
---

diff --git a/regress/usr.sbin/syslogd/args-client-tcp-octet-maxline.pl b/regress/usr.sbin/syslogd/args-client-tcp-octet-maxline.pl
index 584733a1a59..b18dcbffbde 100644
--- a/regress/usr.sbin/syslogd/args-client-tcp-octet-maxline.pl
+++ b/regress/usr.sbin/syslogd/args-client-tcp-octet-maxline.pl
@@ -8,7 +8,7 @@
 
 use strict;
 use warnings;
-use Socket;
+use Socket qw(AF_INET IPPROTO_TCP TCP_NOPUSH);
 use constant MAXLINE => 8192;
 use constant MAX_UDPMSG => 1180;
 
@@ -24,11 +24,15 @@ our %args = (
 	    print STDERR "<<< $msg\n";
 	    ${$self->{syslogd}}->loggrep(qr/tcp logger .* use \d+ bytes/, 5)
 		or die ref($self), " syslogd did not use bytes";
+	    setsockopt(\*STDOUT, IPPROTO_TCP, TCP_NOPUSH, pack('i', 1))
+		or die ref($self), " set TCP_NOPUSH failed: $!";
 	    $msg = generate_chars(MAXLINE);
 	    printf "%05d %s", MAXLINE+1, $msg;
 	    print STDERR "<<< $msg\n";
+	    setsockopt(\*STDOUT, IPPROTO_TCP, TCP_NOPUSH, pack('i', 0))
+		or die ref($self), " clear TCP_NOPUSH failed: $!";
 	    ${$self->{syslogd}}->loggrep("tcp logger .* incomplete", 5)
-		or die ref($self), " syslogd did not receive 2 incomplete";
+		or die ref($self), " syslogd did not receive incomplete";
 	    print "\n";
 	    print STDERR "<<< \n";
 	    write_shutdown($self);