diff --git a/mysqltuner.pl b/mysqltuner.pl
index e0839b6..0703990 100755
--- a/mysqltuner.pl
+++ b/mysqltuner.pl
@@ -3881,9 +3881,9 @@ sub get_pf_memory {
     return 0 unless defined $myvar{'performance_schema'};
     return 0 if $myvar{'performance_schema'} eq 'OFF';
 
-    my @infoPFSMemory = grep /performance_schema.memory/,
+    my @infoPFSMemory = grep { /\tperformance_schema[.]memory\t/msx }
       select_array("SHOW ENGINE PERFORMANCE_SCHEMA STATUS");
-    return 0 if scalar(@infoPFSMemory) == 0;
+    @infoPFSMemory == 1 || return 0;
     $infoPFSMemory[0] =~ s/.*\s+(\d+)$/$1/g;
     return $infoPFSMemory[0];
 }