solver: use async_check for the temporary git repo

While the temporary git repo is likely in cache and not
subject to high seek latency as normal code repos are,
inflating objects still takes a non-trivial amount of time.
So use this as an opportunity to serve other clients and
exploit parallelism in SMP systems.

diff --git a/lib/PublicInbox/SolverGit.pm b/lib/PublicInbox/SolverGit.pm
index 6dd222a9ac08c2ebbf2c984cc60a8d8e4eff5dfa..d50a2fd1c0a8a11bf6adbf69caeb3dd65000ab6f 100644 (file)
--- a/lib/PublicInbox/SolverGit.pm
+++ b/lib/PublicInbox/SolverGit.pm
@@ -385,21 +385,28 @@ EOF
 
 sub do_finish ($) {
        my ($self) = @_;
-       my ($found, $oid_want) = @$self{qw(found oid_want)};
-       if (my $exists = $found->{$oid_want}) {
+       my $oid_want = $self->{oid_want};
+       if (my $exists = $self->{found}->{$oid_want}) {
                return done($self, $exists);
        }
 
        # let git disambiguate if oid_want was too short,
        # but long enough to be unambiguous:
-       my $tmp_git = $self->{tmp_git};
-       if (my @res = $tmp_git->check($oid_want)) {
-               return done($self, $found->{$res[0]});
-       }
-       if (my $err = $tmp_git->last_check_err) {
-               dbg($self, $err);
+       if ($self->{psgi_env}->{'pi-httpd.async'}) {
+               async_check { git => $self->{tmp_git} }, $oid_want,
+                               \&finish_cb, $self
+       } else {
+               my ($hex, $type) = $self->{tmp_git}->check($oid_want);
+               finish_cb(undef, $hex, $type // 'missing', undef, $self)
        }
-       done($self, undef);
+}
+
+sub finish_cb { # async_check cb
+       my (undef, $oid_full, $type, undef, $self) = @_;
+       return done $self, $self->{found}->{$oid_full} if $type eq 'blob';
+       my $err = $self->{tmp_git}->last_check_err;
+       dbg $self, $err if $err;
+       done $self, undef;
 }
 
 sub event_step ($) {
@@ -456,9 +463,10 @@ sub mark_found ($$$) {
 
 sub parse_ls_files ($$) {
        my ($self, $bref) = @_;
-       my ($qsp_err, $di) = delete @$self{qw(-qsp_err -cur_di)};
+       my $qsp_err = delete $self->{-qsp_err};
        die "git ls-files -s -z error:$qsp_err" if $qsp_err;
 
+       my $di = $self->{-cur_di};
        my @ls = split(/\0/, $$bref);
        my ($line, @extra) = grep(/\t\Q$di->{path_b}\E\z/, @ls);
        scalar(@extra) and die "BUG: extra files in index: <",
@@ -469,14 +477,23 @@ sub parse_ls_files ($$) {
        $file eq $di->{path_b} or die
 "BUG: index mismatch: file=$file != path_b=$di->{path_b}";
 
+       dbg($self, "index at:\n$mode_b $oid_b_full\t$file");
        my $tmp_git = $self->{tmp_git} or die 'no git working tree';
-       my (undef, undef, $size) = $tmp_git->check($oid_b_full);
-       defined($size) or die "check $oid_b_full failed";
+       if ($self->{psgi_env}->{'pi-httpd.async'}) {
+               async_check { git => $tmp_git }, $oid_b_full,
+                       \&ck_size_cb, $self
+       } else {
+               ck_size_cb(undef, $tmp_git->check($oid_b_full), $self);
+       }
+}
 
-       dbg($self, "index at:\n$mode_b $oid_b_full\t$file");
-       my $created = [ $tmp_git, $oid_b_full, 'blob', $size, $di ];
-       mark_found($self, $di->{oid_b}, $created);
-       next_step($self); # onto the next patch
+sub ck_size_cb { # async_check cb
+       my (undef, $oid_b_full, undef, $size, $self) = @_;
+       $size // die "check $oid_b_full failed";
+       my $di = delete $self->{-cur_di} // die 'BUG: no -cur_di';
+       my $created = [ $self->{tmp_git}, $oid_b_full, 'blob', $size, $di ];
+       mark_found $self, $di->{oid_b}, $created;
+       next_step $self; # onto the next patch
 }
 
 sub ls_files_result {