From f460f73ac2393401f85845f8df77af9fd0e8f781 Mon Sep 17 00:00:00 2001
From: Jesse Weaver <jweaver@bywatersolutions.com>
Date: Tue, 1 Mar 2016 13:44:22 -0700
Subject: [PATCH] Bug 15350: Cache loaded DBIx::Class schema classes

This separates the Koha::Schema creation into two stages:

 1) The loading of the schemas themselves, which is done upon import of
    Koha::Database. This requires moving the import of Koha::Schema from
    an on-demand `require` to just a `use`; most everything in Koha uses
    C4::Context, which will indirectly end up calling
    Koha::Database->schema->new anyway, so this was no longer saving
    anything.
 2) The actual database connection, which is done by cloning the schema
    created above and adding a database connection.

Note that this saves time only when a Plack-based Koha needs to create
a database connection, which is usually only the case for a new worker.

Unscientific timings before patch:
  * First load of koha2marclinks.pl on a new worker: 0.70 seconds
  * Each load after: 0.17 seconds

After patch:
  * First load: 0.31 seconds
  * Each load after: 0.17 seconds
---
 Koha/Database.pm | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/Koha/Database.pm b/Koha/Database.pm
index a8f4eab..b96918e 100644
--- a/Koha/Database.pm
+++ b/Koha/Database.pm
@@ -35,20 +35,23 @@ Koha::Database
 use Modern::Perl;
 use Carp;
 use C4::Context;
+use Koha::Schema;
 use base qw(Class::Accessor);
 
 use vars qw($database);
 
 __PACKAGE__->mk_accessors(qw( ));
 
+BEGIN {
+    # Initialize the base schema object (just loads the schema classes)
+    $database->{base_schema} = Koha::Schema->clone;
+}
+
 # _new_schema
 # Internal helper function (not a method!). This creates a new
 # database connection from the data given in the current context, and
 # returns it.
 sub _new_schema {
-
-    require Koha::Schema;
-
     my $context = C4::Context->new();
 
     my $db_driver = $context->{db_driver};
@@ -70,7 +73,10 @@ sub _new_schema {
         $encoding_query = "set client_encoding = 'UTF8';";
         $tz_query = qq(SET TIME ZONE = "$tz") if $tz;
     }
-    my $schema = Koha::Schema->connect(
+
+    # This creates a new copy of the schema with its own database handle but with all the schema
+    # classes already loaded.
+    my $schema = $database->{base_schema}->connect(
         {
             dsn => "dbi:$db_driver:database=$db_name;host=$db_host;port=$db_port",
             user => $db_user,
-- 
2.7.0