The epoll implementation is the only one which respects the
limit (kevent would, but IO::KQueue does not). In any case,
I'm not a fan of the maxevents=1000 historical default since
it leads to fairness problems with shared non-blocking listeners
across multiple daemon workers.
---
lib/PublicInbox/DS.pm | 4 ++--
lib/PublicInbox/DSKQXS.pm | 3 ++-
lib/PublicInbox/DSPoll.pm | 2 +-
lib/PublicInbox/Epoll.pm | 5 ++++-
lib/PublicInbox/Select.pm | 2 +-
t/ds-poll.t | 14 +++++++-------
t/epoll.t | 4 ++--
7 files changed, 19 insertions(+), 15 deletions(-)
diff --git a/lib/PublicInbox/DS.pm b/lib/PublicInbox/DS.pm
index b30e9db6..9e1f66c2 100644
--- a/lib/PublicInbox/DS.pm
+++ b/lib/PublicInbox/DS.pm
@@ -287,8 +287,8 @@ sub event_loop (;$$) {
do {
my $timeout = RunTimers();
- # get up to 1000 FDs representing events
- $Poller->ep_wait(1000, $timeout, \@active);
+ # grab whatever FDs are ready
+ $Poller->ep_wait($timeout, \@active);
# map all FDs to their associated Perl object
@active = @DescriptorMap{@active};
diff --git a/lib/PublicInbox/DSKQXS.pm b/lib/PublicInbox/DSKQXS.pm
index 8ef8ffb6..f84c196a 100644
--- a/lib/PublicInbox/DSKQXS.pm
+++ b/lib/PublicInbox/DSKQXS.pm
@@ -117,7 +117,8 @@ sub ep_del {
}
sub ep_wait {
- my ($self, $maxevents, $timeout_msec, $events) = @_;
+ my ($self, $timeout_msec, $events) = @_;
+ # n.b.: IO::KQueue is hard-coded to return up to 1000 events
@$events = eval { $self->{kq}->kevent($timeout_msec) };
if (my $err = $@) {
# workaround https://rt.cpan.org/Ticket/Display.html?id=116615
diff --git a/lib/PublicInbox/DSPoll.pm b/lib/PublicInbox/DSPoll.pm
index 0446df4c..b947f756 100644
--- a/lib/PublicInbox/DSPoll.pm
+++ b/lib/PublicInbox/DSPoll.pm
@@ -18,7 +18,7 @@ use Errno ();
sub new { bless {}, __PACKAGE__ } # fd => events
sub ep_wait {
- my ($self, $maxevents, $timeout_msec, $events) = @_;
+ my ($self, $timeout_msec, $events) = @_;
my (@pset, $n, $fd, $revents, $nval);
while (my ($fd, $events) = each %$self) {
my $pevents = $events & EPOLLIN ? POLLIN : 0;
diff --git a/lib/PublicInbox/Epoll.pm b/lib/PublicInbox/Epoll.pm
index d55c8535..7e0aa6e7 100644
--- a/lib/PublicInbox/Epoll.pm
+++ b/lib/PublicInbox/Epoll.pm
@@ -18,6 +18,9 @@ sub new {
sub ep_add { epoll_ctl(fileno(${$_[0]}), EPOLL_CTL_ADD, fileno($_[1]), $_[2]) }
sub ep_mod { epoll_ctl(fileno(${$_[0]}), EPOLL_CTL_MOD, fileno($_[1]), $_[2]) }
sub ep_del { epoll_ctl(fileno(${$_[0]}), EPOLL_CTL_DEL, fileno($_[1]), 0) }
-sub ep_wait { epoll_wait(fileno(${$_[0]}), @_[1, 2, 3]) }
+
+# n.b. maxevents=1000 is the historical default. maxevents=1 (yes, one)
+# is more fair under load with multiple worker processes sharing one listener
+sub ep_wait { epoll_wait(fileno(${$_[0]}), 1000, @_[1, 2]) }
1;
diff --git a/lib/PublicInbox/Select.pm b/lib/PublicInbox/Select.pm
index 5817c9ef..5cb7aff3 100644
--- a/lib/PublicInbox/Select.pm
+++ b/lib/PublicInbox/Select.pm
@@ -12,7 +12,7 @@ use PublicInbox::Syscall qw(EPOLLONESHOT EPOLLIN EPOLLOUT);
sub new { bless {}, __PACKAGE__ } # fd => events
sub ep_wait {
- my ($self, $maxevents, $msec, $events) = @_;
+ my ($self, $msec, $events) = @_;
my ($rvec, $wvec) = ('', ''); # we don't use EPOLLERR
while (my ($fd, $ev) = each %$self) {
vec($rvec, $fd, 1) = 1 if $ev & EPOLLIN;
diff --git a/t/ds-poll.t b/t/ds-poll.t
index 7a7e2bcf..321534bd 100644
--- a/t/ds-poll.t
+++ b/t/ds-poll.t
@@ -16,33 +16,33 @@ pipe($r, $w);
pipe($x, $y);
is($p->ep_add($r, EPOLLIN), 0, 'add EPOLLIN');
my $events = [];
-$p->ep_wait(9, 0, $events);
+$p->ep_wait(0, $events);
is_deeply($events, [], 'no events set');
is($p->ep_add($w, EPOLLOUT|EPOLLONESHOT), 0, 'add EPOLLOUT|EPOLLONESHOT');
-$p->ep_wait(9, -1, $events);
+$p->ep_wait(-1, $events);
is(scalar(@$events), 1, 'got POLLOUT event');
is($events->[0], fileno($w), '$w ready');
-$p->ep_wait(9, 0, $events);
+$p->ep_wait(0, $events);
is(scalar(@$events), 0, 'nothing ready after oneshot');
is_deeply($events, [], 'no events set after oneshot');
syswrite($w, '1') == 1 or die;
for my $t (0..1) {
- $p->ep_wait(9, $t, $events);
+ $p->ep_wait($t, $events);
is($events->[0], fileno($r), "level-trigger POLLIN ready #$t");
is(scalar(@$events), 1, "only event ready #$t");
}
syswrite($y, '1') == 1 or die;
is($p->ep_add($x, EPOLLIN|EPOLLONESHOT), 0, 'EPOLLIN|EPOLLONESHOT add');
-$p->ep_wait(9, -1, $events);
+$p->ep_wait(-1, $events);
is(scalar @$events, 2, 'epoll_wait has 2 ready');
my @fds = sort @$events;
my @exp = sort((fileno($r), fileno($x)));
is_deeply(\@fds, \@exp, 'got both ready FDs');
is($p->ep_del($r, 0), 0, 'EPOLL_CTL_DEL OK');
-$p->ep_wait(9, 0, $events);
+$p->ep_wait(0, $events);
is(scalar @$events, 0, 'nothing ready after EPOLL_CTL_DEL');
is($p->ep_add($r, EPOLLIN), 0, 're-add');
@@ -54,7 +54,7 @@ SKIP: {
my @w;
eval {
local $SIG{__WARN__} = sub { push @w, @_ };
- $p->ep_wait(9, 0, $events);
+ $p->ep_wait(0, $events);
};
ok($@, 'error detected from bad FD');
ok($!{EBADF}, 'EBADF errno set');
diff --git a/t/epoll.t b/t/epoll.t
index 54dc6f47..ab9ac22a 100644
--- a/t/epoll.t
+++ b/t/epoll.t
@@ -12,11 +12,11 @@ pipe(my $r, my $w);
is($ep->ep_add($w, EPOLLOUT), 0, 'epoll_ctl pipe EPOLLOUT');
my @events;
-$ep->ep_wait(100, 10000, \@events);
+$ep->ep_wait(10000, \@events);
is(scalar(@events), 1, 'got one event');
is($events[0], fileno($w), 'got expected FD');
close $w;
-$ep->ep_wait(100, 0, \@events);
+$ep->ep_wait(0, \@events);
is(scalar(@events), 0, 'epoll_wait timeout');
done_testing;
