[Sqlgrey-users] Performance tuning of update_dbnow

[Michael S. <Mic...@lr...>]

Hi,

if you are working on a new version, you could include this little change
to tune subroutine update_dbnow:

my $old_time = 0; # used for faster dbnow
my $new_time = 0;

--- update_dbnow.old	2009-08-18 12:25:46.618399188 +0200
+++ update_dbnow.new	2009-08-18 12:40:28.486024736 +0200
@@ -1,19 +1,27 @@
 sub update_dbnow($) {
     my $self = shift;

     # no dbnow needed for SQLite
     return if $self->SQLite();

+    # if called in the same second, no update of dbnow needed
+    $new_time = time;
+    if ($new_time == $old_time) {
+	return;
+    } else {
+	$old_time = $new_time;
+    }
+
     my $result;
     my $sth = $self->prepare_cached('SELECT now()');
     if (!defined $sth or !$sth->execute()) {
 	$self->db_unavailable();
 	$self->mylog('dbaccess', 0, "error: couldn't get now() from DB: $DBI::errstr");
 	return if defined $self->{sqlgrey}{dbnow}; # defined: we don't update the value
 	$self->{sqlgrey}{dbnow} = '0';
     } else {
 	$self->db_available();
 	$result = $sth->fetchall_arrayref();
 	$self->{sqlgrey}{dbnow} = $self->quote($result->[0][0]);
     }
 }


Regards,
Michael Storz