Bug 956230: improve instrumentation of bugzilla's internals

Bugzilla.pm

@@ -55,6 +55,10 @@ use Bugzilla::Token;
 use Bugzilla::User;
 use Bugzilla::Util;
 
+use Bugzilla::Metrics::Collector;
+use Bugzilla::Metrics::Template;
+use Bugzilla::Metrics::Memcached;
+
 use File::Basename;
 use File::Spec::Functions;
 use DateTime::TimeZone;
@@ -127,6 +131,30 @@ sub init_page {
 
     my $script = basename($0);
 
+    # BMO - init metrics collection if required
+    if (i_am_cgi() && $script eq 'show_bug.cgi') {
+        # we need to measure loading the params, so default to on
+        Bugzilla->metrics_enabled(1);
+        Bugzilla->metrics($script);
+        # we can now hit params to check if we really should be enabled.
+        # note - we can't use anything which uses templates or the database, as
+        # that would initialise those modules with metrics enabled.
+        if (!Bugzilla->params->{metrics_enabled}) {
+            Bugzilla->metrics_enabled(0);
+        }
+        else {
+            # to avoid generating massive amounts of data, we're only interested in
+            # a small subset of users
+            my $user_id = Bugzilla->cgi->cookie('Bugzilla_login');
+            if (!$user_id
+                || !grep { $user_id == $_ }
+                    split(/\s*,\s*/, Bugzilla->params->{metrics_user_ids}))
+            {
+                Bugzilla->metrics_enabled(0);
+            }
+        }
+    }
+
     # Because of attachment_base, attachment.cgi handles this itself.
     if ($script ne 'attachment.cgi') {
         do_ssl_redirect_if_required();
@@ -195,7 +223,12 @@ sub init_page {
 #####################################################################
 
 sub template {
-    return $_[0]->request_cache->{template} ||= Bugzilla::Template->create();
+    # BMO - use metrics subclass if required
+    if (Bugzilla->metrics_enabled) {
+        return $_[0]->request_cache->{template} ||= Bugzilla::Metrics::Template->create();
+    } else {
+        return $_[0]->request_cache->{template} ||= Bugzilla::Template->create();
+    }
 }
 
 sub template_inner {
@@ -660,17 +693,43 @@ sub process_cache {
     return $_process_cache;
 }
 
+# BMO - Instrumentation
+
+sub metrics_enabled {
+    if (defined $_[1]) {
+        $_[0]->request_cache->{metrics_enabled} = $_[1];
+        delete $_[0]->request_cache->{metrics} unless $_[1];
+    }
+    else {
+        return $_[0]->request_cache->{metrics_enabled};
+    }
+}
+
+sub metrics {
+    return $_[0]->request_cache->{metrics} ||= Bugzilla::Metrics::Collector->new($_[1]);
+}
+
 # This is a memcached wrapper, which provides cross-process and cross-system
 # caching.
 sub memcached {
-    return $_[0]->process_cache->{memcached} ||= Bugzilla::Memcached->_new();
+    # BMO - use metrics subclass if required
+    if (Bugzilla->metrics_enabled) {
+        return $_[0]->request_cache->{memcached} ||= Bugzilla::Metrics::Memcached->_new();
+    } else {
+        return $_[0]->request_cache->{memcached} ||= Bugzilla::Memcached->_new();
+    }
 }
 
 # Private methods
 
 # Per-process cleanup. Note that this is a plain subroutine, not a method,
 # so we don't have $class available.
 sub _cleanup {
+    # BMO - finalise and report on metrics
+    if (Bugzilla->metrics_enabled) {
+        Bugzilla->metrics->finish();
+    }
+
     my $main   = Bugzilla->request_cache->{dbh_main};
     my $shadow = Bugzilla->request_cache->{dbh_shadow};
     foreach my $dbh ($main, $shadow) {

Bugzilla/Config/Advanced.pm

@@ -75,6 +75,37 @@ use constant get_param_list => (
    type => 't',
    default => '',
   },
+
+  {
+   name => 'metrics_enabled',
+   type => 'b',
+   default => 0
+  },
+  {
+   name => 'metrics_user_ids',
+   type => 't',
+   default => '3881,5038,5898,13647,20209,251051,373476,409787'
+  },
+  {
+   name => 'metrics_elasticsearch_server',
+   type => 't',
+   default => '127.0.0.1:9200'
+  },
+  {
+   name => 'metrics_elasticsearch_index',
+   type => 't',
+   default => 'bmo-metrics'
+  },
+  {
+   name => 'metrics_elasticsearch_type',
+   type => 't',
+   default => 'timings'
+  },
+  {
+   name => 'metrics_elasticsearch_ttl',
+   type => 't',
+   default => '1210000000' # 14 days
+  },
 );
 
 1;

Bugzilla/DB.pm

@@ -43,6 +43,8 @@ use Bugzilla::Util;
 use Bugzilla::Error;
 use Bugzilla::DB::Schema;
 
+use Bugzilla::Metrics::Mysql;
+
 use List::Util qw(max);
 use Storable qw(dclone);
 
@@ -148,6 +150,12 @@ sub _connect {
                 . " localconfig: " . $@);
 
     # instantiate the correct DB specific module
+
+    # BMO - enable instrumentation of db calls
+    if (Bugzilla->metrics_enabled) {
+        $pkg_module = 'Bugzilla::Metrics::Mysql';
+    }
+
     my $dbh = $pkg_module->new($params);
 
     return $dbh;

Bugzilla/Install/Filesystem.pm

@@ -160,6 +160,7 @@ sub FILESYSTEM {
         'jobqueue.pl'     => { perms => OWNER_EXECUTE },
         'migrate.pl'      => { perms => OWNER_EXECUTE },
         'sentry.pl'       => { perms => OWNER_EXECUTE },
+        'metrics.pl'      => { perms => OWNER_EXECUTE },
         'install-module.pl' => { perms => OWNER_EXECUTE },
 
         'Bugzilla.pm'   => { perms => CGI_READ },

Bugzilla/Install/Requirements.pm

@@ -386,6 +386,13 @@ sub OPTIONAL_MODULES {
         version => '0',
         feature => ['memcached'],
     },
+
+    # BMO - metrics
+    {
+        package => 'ElasticSearch',
+        module  => 'ElasticSearch',
+        version => '0',
+    },
     );
 
     my $extra_modules = _get_extension_requirements('OPTIONAL_MODULES');