Materialize the number of finished builds

The NrBuilds table tracks the value of ‘select count(*) from Builds
where finished = 0’, keeping it up to date via a trigger.  This is
necessary to make the /all page fast, since otherwise it needs to do a
sequential scan on the Builds table.

src/lib/Hydra/Base/Controller/ListBuilds.pm

@@ -56,13 +56,12 @@ sub all : Chained('get_builds') PathPart {
 
     my $resultsPerPage = 20;
 
-    my $nrBuilds = $c->stash->{allBuilds}->search({finished => 1})->count;
-
     $c->stash->{baseUri} = $c->uri_for($self->action_for("all"), $c->req->captures);
 
     $c->stash->{page} = $page;
     $c->stash->{resultsPerPage} = $resultsPerPage;
-    $c->stash->{total} = $nrBuilds;
+    $c->stash->{total} = $c->stash->{allBuilds}->search({finished => 1})->count
+        unless defined $c->stash->{total};
 
     $c->stash->{builds} = [ $c->stash->{allBuilds}->search(
         { finished => 1 },

src/lib/Hydra/Controller/Root.pm

@@ -155,6 +155,7 @@ sub get_builds : Chained('/') PathPart('') CaptureArgs(0) {
     $c->stash->{allJobs} = $c->model('DB::Jobs');
     $c->stash->{latestSucceeded} = $c->model('DB')->resultset('LatestSucceeded');
     $c->stash->{channelBaseName} = "everything";
+    $c->stash->{total} = $c->model('DB::NrBuilds')->find('finished')->count;
 }
 
 

src/lib/Hydra/Schema/NrBuilds.pm

@@ -0,0 +1,75 @@
+use utf8;
+package Hydra::Schema::NrBuilds;
+
+# Created by DBIx::Class::Schema::Loader
+# DO NOT MODIFY THE FIRST PART OF THIS FILE
+
+=head1 NAME
+
+Hydra::Schema::NrBuilds
+
+=cut
+
+use strict;
+use warnings;
+
+use base 'DBIx::Class::Core';
+
+=head1 COMPONENTS LOADED
+
+=over 4
+
+=item * L<Hydra::Component::ToJSON>
+
+=back
+
+=cut
+
+__PACKAGE__->load_components("+Hydra::Component::ToJSON");
+
+=head1 TABLE: C<NrBuilds>
+
+=cut
+
+__PACKAGE__->table("NrBuilds");
+
+=head1 ACCESSORS
+
+=head2 what
+
+  data_type: 'text'
+  is_nullable: 0
+
+=head2 count
+
+  data_type: 'integer'
+  is_nullable: 0
+
+=cut
+
+__PACKAGE__->add_columns(
+  "what",
+  { data_type => "text", is_nullable => 0 },
+  "count",
+  { data_type => "integer", is_nullable => 0 },
+);
+
+=head1 PRIMARY KEY
+
+=over 4
+
+=item * L</what>
+
+=back
+
+=cut
+
+__PACKAGE__->set_primary_key("what");
+
+
+# Created by DBIx::Class::Schema::Loader v0.07033 @ 2013-08-12 17:59:18
+# DO NOT MODIFY THIS OR ANYTHING ABOVE! md5sum:CK8eJGC803nGj0wnete9xg
+
+
+# You can replace this text with custom code or comments, and it will be preserved on regeneration
+1;

src/script/hydra-init

@@ -51,12 +51,12 @@ for (my $n = $schemaVersion; $n < $maxSchemaVersion; $n++) {
     my @statements = $sql_splitter->split($schema);
     eval {
         $dbh->begin_work;
-        sub run {
+        sub run_ {
             my ($stm) = @_;
             print STDERR "executing SQL statement: $stm\n";
             $dbh->do($_);
         }
-        run($_) foreach @statements;
+        run_($_) foreach @statements;
         $db->resultset('SchemaVersion')->update({version => $m});
         $dbh->commit;
     };

src/sql/hydra.sql

@@ -514,6 +514,36 @@ create table NewsItems (
 );
 
 
+-- Cache of the number of finished builds.
+create table NrBuilds (
+    what  text primary key not null,
+    count integer not null
+);
+
+insert into NrBuilds(what, count) values('finished', 0);
+
+#ifdef POSTGRESQL
+
+create function modifyNrBuildsFinished() returns trigger as $$
+  begin
+    if ((tg_op = 'INSERT' and new.finished = 1) or
+        (tg_op = 'UPDATE' and old.finished = 0 and new.finished = 1)) then
+      update NrBuilds set count = count + 1 where what = 'finished';
+    elsif ((tg_op = 'DELETE' and old.finished = 1) or
+           (tg_op = 'UPDATE' and old.finished = 1 and new.finished = 0)) then
+      update NrBuilds set count = count - 1 where what = 'finished';
+    end if;
+    return null;
+  end;
+$$ language plpgsql;
+
+create trigger NrBuildsFinished after insert or update or delete on Builds
+  for each row
+  execute procedure modifyNrBuildsFinished();
+
+#endif
+
+
 -- Some indices.
 
 create index IndexBuildInputsOnBuild on BuildInputs(build);
@@ -534,7 +564,7 @@ create index IndexBuildsOnJobAndSystem on Builds(project, jobset, job, system);
 create index IndexBuildsOnJobset on Builds(project, jobset);
 create index IndexBuildsOnProject on Builds(project);
 create index IndexBuildsOnTimestamp on Builds(timestamp);
-create index IndexBuildsOnJobsetFinishedTimestamp on Builds(project, jobset, finished, timestamp DESC);
+create index IndexBuildsOnJobsetFinishedTimestamp on Builds(project, jobset, finished, timestamp DESC); -- obsolete?
 create index IndexBuildsOnJobFinishedId on builds(project, jobset, job, system, finished, id DESC);
 create index IndexBuildsOnJobSystemCurrent on Builds(project, jobset, job, system, isCurrent);
 create index IndexBuildsOnDrvPath on Builds(drvPath);

src/sql/upgrade-17.sql

@@ -0,0 +1,23 @@
+create table NrBuilds (
+    what  text primary key not null,
+    count integer not null
+);
+
+create function modifyNrBuildsFinished() returns trigger as $$
+  begin
+    if ((tg_op = 'INSERT' and new.finished = 1) or
+        (tg_op = 'UPDATE' and old.finished = 0 and new.finished = 1)) then
+      update NrBuilds set count = count + 1 where what = 'finished';
+    elsif ((tg_op = 'DELETE' and old.finished = 1) or
+           (tg_op = 'UPDATE' and old.finished = 1 and new.finished = 0)) then
+      update NrBuilds set count = count - 1 where what = 'finished';
+    end if;
+    return null;
+  end;
+$$ language plpgsql;
+
+create trigger NrBuildsFinished after insert or update or delete on Builds
+  for each row
+  execute procedure modifyNrBuildsFinished();
+
+insert into NrBuilds(what, count) select 'finished', count(*) from Builds where finished = 1;

tests/query-all-tables.pl

@@ -7,11 +7,11 @@ my $db = Hydra::Model::DB->new;
 my @sources = $db->schema->sources;
 my $nrtables = scalar(@sources);
 
-use Test::Simple tests => 43;
+use Test::Simple tests => 44;
 
 foreach my $source (@sources) {
     my $title = "Basic select query for $source";
-    if ($source eq "SchemaVersion") {
+    if ($source eq "SchemaVersion" || $source eq "NrBuilds") {
         ok(scalar($db->resultset($source)->all) == 1, $title);
     } elsif( $source !~ m/^(LatestSucceeded|JobStatus|ActiveJobs)/) {
         ok(scalar($db->resultset($source)->all) == 0, $title);