diff --git a/lib/gitlab_monitor/memstats.rb b/lib/gitlab_monitor/memstats.rb
index ae2212978cf643731f4905d6b92dc4700af8226b..1eb37aa8c5d43307a260ea92c73d0967140815c1 100644
--- a/lib/gitlab_monitor/memstats.rb
+++ b/lib/gitlab_monitor/memstats.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative "memstats/mapping"
 
 # Ported from https://github.com/discourse/discourse/blob/master/script/memstats.rb
diff --git a/lib/gitlab_monitor/memstats/mapping.rb b/lib/gitlab_monitor/memstats/mapping.rb
index 40b1342b8087ba807b1d2d8a0bad862310ccb3ef..baddaa22a259ee4aef6b3087090e61a5179e9d89 100644
--- a/lib/gitlab_monitor/memstats/mapping.rb
+++ b/lib/gitlab_monitor/memstats/mapping.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module GitLab
   module Monitor
     module MemStats
@@ -56,7 +58,9 @@ module GitLab
         end
 
         def parse_first_line(line)
-          parts = line.strip.split
+          line.strip!
+
+          parts = line.split
           @address_start, @address_end = parts[0].split("-")
           @perms = parts[1]
           @offset = parts[2]
@@ -66,8 +70,15 @@ module GitLab
         end
 
         def parse_field_line(line)
-          parts = line.strip.split
-          field = parts[0].downcase.sub(":", "")
+          line.strip!
+
+          parts = line.split
+
+          return unless parts
+
+          parts[0].downcase!
+          parts[0].sub!(":", "")
+          field = parts[0]
 
           return unless respond_to? "#{field}="
 
diff --git a/lib/gitlab_monitor/process.rb b/lib/gitlab_monitor/process.rb
index 335b9040b9bb31afd81284bc7d093bc20f3897d3..b11345bc2b9dc0e2f1bff4024022824bba96bfb8 100644
--- a/lib/gitlab_monitor/process.rb
+++ b/lib/gitlab_monitor/process.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative "memstats"
 
 module GitLab