inboxidle: clue users into resolving ENOSPC from inotify

[public-inbox.git] / lib / PublicInbox / InboxIdle.pm

diff --git a/lib/PublicInbox/InboxIdle.pm b/lib/PublicInbox/InboxIdle.pm
index 97e9d53250eb43285ae7eba56c3f4ae79d898d8e..357bd216b5c30642fef65c84bbd343053d53ec25 100644 (file)
--- a/lib/PublicInbox/InboxIdle.pm
+++ b/lib/PublicInbox/InboxIdle.pm
@@ -1,12 +1,14 @@
 # Copyright (C) 2020 all contributors <meta@public-inbox.org>
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
 
+# fields:
+# pi_config: PublicInbox::Config ref
+# inot: Linux::Inotify2-like object
+# pathmap => { inboxdir => [ ibx, watch1, watch2, watch3... ] } mapping
 package PublicInbox::InboxIdle;
 use strict;
-use base qw(PublicInbox::DS);
-use fields qw(pi_config inot pathmap);
+use parent qw(PublicInbox::DS);
 use Cwd qw(abs_path);
-use Symbol qw(gensym);
 use PublicInbox::Syscall qw(EPOLLIN EPOLLET);
 my $IN_MODIFY = 0x02; # match Linux inotify
 my $ino_cls;
@@ -34,12 +36,21 @@ sub in2_arm ($$) { # PublicInbox::Config::each_inbox callback
                $ibx->{unlock_subs} and
                        die "BUG: $dir->{unlock_subs} should not exist";
                $ibx->{unlock_subs} = $old_ibx->{unlock_subs};
-               $cur->[1]->cancel;
+               $cur->[1]->cancel; # Linux::Inotify2::Watch::cancel
        }
        $cur->[0] = $ibx;
 
        my $lock = "$dir/".($ibx->version >= 2 ? 'inbox.lock' : 'ssoma.lock');
-       $cur->[1] = $inot->watch($lock, $IN_MODIFY, sub { $ibx->on_unlock });
+       if (my $w = $cur->[1] = $inot->watch($lock, $IN_MODIFY)) {
+               $self->{on_unlock}->{$w->name} = $ibx;
+       } else {
+               warn "E: ".ref($inot)."->watch($lock, IN_MODIFY) failed: $!\n";
+               if ($!{ENOSPC} && $^O eq 'linux') {
+                       warn <<"";
+I: consider increasing /proc/sys/fs/inotify/max_user_watches
+
+               }
+       }
 
        # TODO: detect deleted packs (and possibly other files)
 }
@@ -51,32 +62,36 @@ sub refresh {
 
 sub new {
        my ($class, $pi_config) = @_;
-       my $self = fields::new($class);
+       my $self = bless {}, $class;
        my $inot;
        if ($ino_cls) {
                $inot = $ino_cls->new or die "E: $ino_cls->new: $!";
-               my $sock = gensym;
-               tie *$sock, 'PublicInbox::In2Tie', $inot;
-               $inot->blocking(0);
-               if ($inot->can('on_overflow')) {
-                        # broadcasts everything on overflow
-                       $inot->on_overflow(undef);
-               }
-               $self->SUPER::new($sock, EPOLLIN | EPOLLET);
+               my $io = PublicInbox::In2Tie::io($inot);
+               $self->SUPER::new($io, EPOLLIN | EPOLLET);
        } else {
                require PublicInbox::FakeInotify;
                $inot = PublicInbox::FakeInotify->new;
        }
        $self->{inot} = $inot;
        $self->{pathmap} = {}; # inboxdir => [ ibx, watch1, watch2, watch3...]
+       $self->{on_unlock} = {}; # lock path => ibx
        refresh($self, $pi_config);
+       PublicInbox::FakeInotify::poll_once($self) if !$ino_cls;
        $self;
 }
 
 sub event_step {
        my ($self) = @_;
-       eval { $self->{inot}->poll }; # Linux::Inotify2::poll
-       warn "$self->{inot}->poll err: $@\n" if $@;
+       eval {
+               my @events = $self->{inot}->read; # Linux::Inotify2::read
+               my $on_unlock = $self->{on_unlock};
+               for my $ev (@events) {
+                       if (my $ibx = $on_unlock->{$ev->fullname}) {
+                               $ibx->on_unlock;
+                       }
+               }
+       };
+       warn "{inot}->read err: $@\n" if $@;
 }
 
 # for graceful shutdown in PublicInbox::Daemon,