From: Eric Wong <e@80x24.org>
To: meta@public-inbox.org
Subject: [PATCH 12/12] httpd/async: switch to level-triggered epoll
Date: Sat, 16 Oct 2021 01:01:03 +0000 [thread overview]
Message-ID: <20211016010103.30825-13-e@80x24.org> (raw)
In-Reply-To: <20211016010103.30825-1-e@80x24.org>
We'll save ourselves some code here and let the kernel do more
work, instead.
---
Documentation/technical/ds.txt | 3 +--
lib/PublicInbox/HTTPD/Async.pm | 16 +++++-----------
lib/PublicInbox/Qspawn.pm | 1 -
3 files changed, 6 insertions(+), 14 deletions(-)
diff --git a/Documentation/technical/ds.txt b/Documentation/technical/ds.txt
index 7bc1ad79ce0c..5a1655a1450e 100644
--- a/Documentation/technical/ds.txt
+++ b/Documentation/technical/ds.txt
@@ -77,8 +77,7 @@ New features
which (if any) events it's interested in for the next loop iteration.
* Edge-triggering available via EPOLLET or EV_CLEAR. These reduce wakeups
- for unidirectional classes (e.g. PublicInbox::Listener sockets,
- and pipes via PublicInbox::HTTPD::Async).
+ for unidirectional classes when throughput is more important than fairness.
* IO::Socket::SSL support (for NNTPS, STARTTLS+NNTP, HTTPS)
diff --git a/lib/PublicInbox/HTTPD/Async.pm b/lib/PublicInbox/HTTPD/Async.pm
index 7238650aff97..1651da88ac03 100644
--- a/lib/PublicInbox/HTTPD/Async.pm
+++ b/lib/PublicInbox/HTTPD/Async.pm
@@ -17,7 +17,7 @@ package PublicInbox::HTTPD::Async;
use strict;
use parent qw(PublicInbox::DS);
use Errno qw(EAGAIN);
-use PublicInbox::Syscall qw(EPOLLIN EPOLLET);
+use PublicInbox::Syscall qw(EPOLLIN);
# This is called via: $env->{'pi-httpd.async'}->()
# $io is a read-only pipe ($rpipe) for now, but may be a
@@ -39,7 +39,7 @@ sub new {
}, $class;
my $pp = tied *$io;
$pp->{fh}->blocking(0) // die "$io->blocking(0): $!";
- $self->SUPER::new($io, EPOLLIN | EPOLLET);
+ $self->SUPER::new($io, EPOLLIN);
}
sub event_step {
@@ -54,15 +54,12 @@ sub event_step {
my $r = sysread($sock, my $buf, 65536);
if ($r) {
$self->{fh}->write($buf); # may call $http->close
- if ($http->{sock}) { # !closed
- $self->requeue;
- # let other clients get some work done, too
- return;
- }
+ # let other clients get some work done, too
+ return if $http->{sock}; # !closed
# else: fall through to close below...
} elsif (!defined $r && $! == EAGAIN) {
- return; # EPOLLET means we'll be notified
+ return; # EPOLLIN means we'll be notified
}
# Done! Error handling will happen in $self->{fh}->close
@@ -89,9 +86,6 @@ sub async_pass {
$self->{http} = $http;
$self->{fh} = $fh;
-
- # either hit EAGAIN or ->requeue to keep EPOLLET happy
- event_step($self);
}
# may be called as $forward->close in PublicInbox::HTTP or EOF (event_step)
diff --git a/lib/PublicInbox/Qspawn.pm b/lib/PublicInbox/Qspawn.pm
index a1ff65b65324..53d0ad55ee84 100644
--- a/lib/PublicInbox/Qspawn.pm
+++ b/lib/PublicInbox/Qspawn.pm
@@ -192,7 +192,6 @@ sub event_step {
sub rd_hdr ($) {
my ($self) = @_;
# typically used for reading CGI headers
- # we must loop until EAGAIN for EPOLLET in HTTPD/Async.pm
# We also need to check EINTR for generic PSGI servers.
my $ret;
my $total_rd = 0;
next prev parent reply other threads:[~2021-10-16 1:01 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-16 1:00 [PATCH 00/16] some yak-shaving and annoyance fixes Eric Wong
2021-10-16 1:00 ` [PATCH 01/12] smsg: add ->oidbin method Eric Wong
2021-10-16 1:00 ` [PATCH 02/12] dir_idle: do not add watches in ->new Eric Wong
2021-10-16 1:00 ` [PATCH 03/12] imapd+nntpd: drop timer-based expiration Eric Wong
2021-10-16 1:00 ` [PATCH 04/12] httpd: move pipeline logic into event_step Eric Wong
2021-10-16 1:00 ` [PATCH 05/12] lei: golf PATH2CFG cleanup Eric Wong
2021-10-16 1:00 ` [PATCH 06/12] lei: always keep cwd fd {3} for ->fchdir Eric Wong
2021-10-16 1:00 ` [PATCH 07/12] lei: more eval guards for die on failure Eric Wong
2021-10-16 1:00 ` [PATCH 08/12] extindex: prune invalid alternate entries on --gc Eric Wong
2021-10-16 1:01 ` [PATCH 09/12] lei_overview: die rather than lei->fail Eric Wong
2021-10-16 1:01 ` [PATCH 10/12] lei_to_mail: quiet down abort messages Eric Wong
2021-10-16 1:01 ` [PATCH 11/12] inbox + search: use 5.10.1 and do some golfing Eric Wong
2021-10-16 1:01 ` Eric Wong [this message]
2021-10-16 1:42 ` [PATCH 00/12] some yak-shaving and annoyance fixes Eric Wong
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