diff --git a/debian/patches/12_check_snmp_mem_perf b/debian/patches/12_check_snmp_mem_perf
new file mode 100644
index 0000000..3e5c7c8
--- /dev/null
+++ b/debian/patches/12_check_snmp_mem_perf
@@ -0,0 +1,85 @@
+From 8855b778e5a4aa53667baaad3863112fd93aee64 Mon Sep 17 00:00:00 2001
+From: jimbobmcgee <jimbobmcgee@users.noreply.github.com>
+Date: Tue, 20 Mar 2018 23:22:09 +0000
+Subject: [PATCH] Better support for buffered/cached memory in Linux
+
+Exclude buffered memory from perfdata output, if `-b` option is specified
+--------------------------------------------------------------------------
+
+Status output show RAM usage as percentage, while perfdata output shows total literal ram usage.  If `-N -m` options are given, cached memory is included in both the plugin status output and the perfdata.  If `-N -b` options are given, buffered memory is *excluded* from the status output, but remains *included* in the perfdata.
+
+This patch alters the behaviour of the `-N -b` option combination so that, if supplied, buffered memory is also excluded from the perfdata.
+
+
+Add separate perfdata counters for cached and buffered memory, if `-ff` options is specified
+---------------------------------------------------------------------------------------------
+
+Changed `Getopt` behaviour for `-f` so it can be specified more than once.  If it is specified twice, perfdata is extended to include buffered and cached memory readings as separate perfdata values, e.g. `ram_used=12345 buffered=1234 cached=1234`.  If using `-ff`, neither buffered nor cached memory are included in the perfdata value for RAM used.
+---
+ plugins/check_snmp_mem.pl | 24 +++++++++++++-----------
+ 1 file changed, 13 insertions(+), 11 deletions(-)
+
+diff --git a/plugins/check_snmp_mem.pl b/plugins/check_snmp_mem.pl
+index 2ac7ec9..3f93a20 100755
+--- a/plugins/check_snmp_mem.pl
++++ b/plugins/check_snmp_mem.pl
+@@ -95,7 +95,7 @@
+ 
+ sub print_usage {
+     print
+-"Usage: $0 [-v] -H <host> -C <snmp_community> [-2] | (-l login -x passwd [-X pass -L <authp>,<privp>])  [-p <port>] [-P <protocol>] -w <warn level> -c <crit level> [-I|-N|-E] [-f] [-m -b] [-t <timeout>] [-V]\n";
++"Usage: $0 [-v] -H <host> -C <snmp_community> [-2] | (-l login -x passwd [-X pass -L <authp>,<privp>])  [-p <port>] [-P <protocol>] -w <warn level> -c <crit level> [-I|-N|-E] [-f[f]] [-m -b] [-t <timeout>] [-V]\n";
+ }
+ 
+ sub isnnum {                     # Return true if arg is not a number
+@@ -218,8 +218,8 @@ sub check_options {
+         'memcache'    => \$o_cache,
+         'b'           => \$o_buffer,
+         'membuffer'   => \$o_buffer,
+-        'f'           => \$o_perf,
+-        'perfdata'    => \$o_perf
++        'f+'          => \$o_perf,
++        'perfdata+'   => \$o_perf
+     );
+     if (defined($o_help))    { help();      exit $ERRORS{"UNKNOWN"} }
+     if (defined($o_version)) { p_version(); exit $ERRORS{"UNKNOWN"} }
+@@ -578,9 +578,7 @@ sub check_options {
+ 
+     $realused = ($$resultat{$nets_ram_total} - ($$resultat{$nets_ram_free} + $totalcachedbuffered))
+         / $$resultat{$nets_ram_total};
+-
+     if ($$resultat{$nets_ram_total} == 0) { $realused = 0; }
+-
+     $swapused
+         = ($$resultat{$nets_swap_total} == 0)
+         ? 0
+@@ -605,12 +603,11 @@ sub check_options {
+     }
+     $n_output .= " ; " . $n_status;
+     if (defined($o_perf)) {
+-        if (defined($o_cache)) {
+-            $n_output .= " | ram_used=" . ($$resultat{$nets_ram_total} - $$resultat{$nets_ram_free}) . ";";
+-        } else {
+-            $n_output .= " | ram_used="
+-                . ($$resultat{$nets_ram_total} - $$resultat{$nets_ram_free} - $$resultat{$nets_ram_cache}) . ";";
+-        }
++        my $perf_ramused = ($$resultat{$nets_ram_total} - $$resultat{$nets_ram_free});
++        $perf_ramused -= $$resultat{$nets_ram_cache}  if $o_perf > 1 or !defined($o_cache);
++        $perf_ramused -= $$resultat{$nets_ram_buffer} if $o_perf > 1 or defined($o_buffer);
++
++        $n_output .= " | ram_used=$perf_ramused;";
+         $n_output .= ($o_warnR == 0) ? ";" : round($o_warnR * $$resultat{$nets_ram_total} / 100, 0) . ";";
+         $n_output .= ($o_critR == 0) ? ";" : round($o_critR * $$resultat{$nets_ram_total} / 100, 0) . ";";
+         $n_output .= "0;" . $$resultat{$nets_ram_total} . " ";
+@@ -618,6 +615,11 @@ sub check_options {
+         $n_output .= ($o_warnS == 0) ? ";" : round($o_warnS * $$resultat{$nets_swap_total} / 100, 0) . ";";
+         $n_output .= ($o_critS == 0) ? ";" : round($o_critS * $$resultat{$nets_swap_total} / 100, 0) . ";";
+         $n_output .= "0;" . $$resultat{$nets_swap_total};
++
++        if ($o_perf > 1) {
++            $n_output .= " buffered=" . $$resultat{$nets_ram_buffer} . ';;;0;' . $$resultat{$nets_ram_total};
++            $n_output .= " cached="   . $$resultat{$nets_ram_cache}  . ';;;0;' . $$resultat{$nets_ram_total};
++        }
+     }
+     $session->close;
+     print "$n_output \n";
diff --git a/debian/patches/series b/debian/patches/series
index 9a563e9..59501c0 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -1,4 +1,5 @@
 10_check_snmp_storage_error_handling
 11_check_snmp_int_agent_workaround
+12_check_snmp_mem_perf
 50_disable_epn
 51_fix_privacy_doc