From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: X-Spam-Status: No, score=-3.9 required=3.0 tests=ALL_TRUSTED,BAYES_00, RP_MATCHES_RCVD shortcircuit=no autolearn=unavailable version=3.3.2 X-Original-To: meta@public-inbox.org Received: from localhost (dcvr.yhbt.net [127.0.0.1]) by dcvr.yhbt.net (Postfix) with ESMTP id 981571F980 for ; Fri, 29 Apr 2016 07:12:54 +0000 (UTC) From: Eric Wong To: meta@public-inbox.org Subject: [PATCH] http: avoid corking on "Content-Length: 0" response Date: Fri, 29 Apr 2016 07:12:54 +0000 Message-Id: <20160429071254.18163-1-e@80x24.org> List-Id: We must use a normal write instead of send(.., MSG_MORE) when writing responses of "Content-Length: 0" to avoid the corking effect MSG_MORE provides. We only want to cork headers if we will send a non-empty body. Fixes: c3eeaf664cf0 ("http: clarify intent for persistence") This needs a proper test. --- lib/PublicInbox/HTTP.pm | 11 ++++++----- t/httpd-corner.psgi | 2 ++ t/httpd-corner.t | 13 +++++++++++++ 3 files changed, 21 insertions(+), 5 deletions(-) diff --git a/lib/PublicInbox/HTTP.pm b/lib/PublicInbox/HTTP.pm index 3934512..c7fb954 100644 --- a/lib/PublicInbox/HTTP.pm +++ b/lib/PublicInbox/HTTP.pm @@ -151,7 +151,7 @@ sub response_header_write { my $proto = $env->{SERVER_PROTOCOL} or return; # HTTP/0.9 :P my $status = $res->[0]; my $h = "$proto $status " . status_message($status) . "\r\n"; - my $term; + my ($len, $chunked); my $headers = $res->[1]; for (my $i = 0; $i < @$headers; $i += 2) { @@ -159,14 +159,15 @@ sub response_header_write { my $v = $headers->[$i + 1]; next if $k =~ /\A(?:Connection|Date)\z/i; - if ($k =~ /\AContent-Length\z/ || - ($k =~ /\ATransfer-Encoding\z/i && $v =~ /\bchunked\b/i)) { - $term = 1; + $len = $v if $k =~ /\AContent-Length\z/i; + if ($k =~ /\ATransfer-Encoding\z/i && $v =~ /\bchunked\b/i) { + $chunked = 1; } $h .= "$k: $v\r\n"; } my $conn = $env->{HTTP_CONNECTION} || ''; + my $term = defined($len) || $chunked; my $alive = $term && (($proto eq 'HTTP/1.1' && $conn !~ /\bclose\b/i) || ($conn =~ /\bkeep-alive\b/i)); @@ -174,7 +175,7 @@ sub response_header_write { $h .= 'Connection: ' . ($alive ? 'keep-alive' : 'close'); $h .= "\r\nDate: " . http_date() . "\r\n\r\n"; - if ($term && $env->{REQUEST_METHOD} ne 'HEAD') { + if (($len || $chunked) && $env->{REQUEST_METHOD} ne 'HEAD') { more($self, $h); } else { $self->write($h); diff --git a/t/httpd-corner.psgi b/t/httpd-corner.psgi index da8a2ee..2f7be83 100644 --- a/t/httpd-corner.psgi +++ b/t/httpd-corner.psgi @@ -56,6 +56,8 @@ my $app = sub { $fh->write($buf); $fh->close; } + } elsif ($path eq '/empty') { + $code = 200; } [ $code, $h, $body ] diff --git a/t/httpd-corner.t b/t/httpd-corner.t index b64f334..b9eaa6f 100644 --- a/t/httpd-corner.t +++ b/t/httpd-corner.t @@ -5,6 +5,7 @@ use strict; use warnings; use Test::More; +use Time::HiRes qw(gettimeofday tv_interval); foreach my $mod (qw(Plack::Util Plack::Request Plack::Builder Danga::Socket HTTP::Date HTTP::Status)) { @@ -275,6 +276,18 @@ SKIP: { } { + my $conn = conn_for($sock, 'no TCP_CORK on empty body'); + $conn->write("GET /empty HTTP/1.1\r\nHost:example.com\r\n\r\n"); + my $buf = ''; + my $t0 = [ gettimeofday ]; + until ($buf =~ /\r\n\r\n/s) { + $conn->sysread($buf, 4096, length($buf)); + } + my $elapsed = tv_interval($t0, [ gettimeofday ]); + ok($elapsed < 0.190, 'no 200ms TCP cork delay on empty body'); +} + +{ my $conn = conn_for($sock, 'graceful termination during slow request'); $conn->write("PUT /sha1 HTTP/1.0\r\n"); delay(); -- EW