diff --git a/.gitignore b/.gitignore
index a356406..cfae693 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,4 @@
 Gemfile.lock
 FileList
 .scannerwork
+.vscode
\ No newline at end of file
diff --git a/.vscode/settings.json b/.vscode/settings.json
index 403056c..c808a20 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -1,6 +1,8 @@
 {
     "cSpell.words": [
         "changeme",
+        "GOMAXPROCS",
+        "procs",
         "reqpackage",
         "rpms",
         "sslcacert",
diff --git a/doc/puppet_classes/prometheus_cd_3A_3Aparams.html b/doc/puppet_classes/prometheus_cd_3A_3Aparams.html
index 28973b8..9ca1221 100644
--- a/doc/puppet_classes/prometheus_cd_3A_3Aparams.html
+++ b/doc/puppet_classes/prometheus_cd_3A_3Aparams.html
@@ -376,6 +376,96 @@
         —
         <div class='inline'>
 <p>WAL segment size</p>
+</div>
+      
+    </li>
+  
+    <li>
+      
+        <span class='name'>ps_max_mem</span>
+      
+      
+        <span class='type'>(<tt>String</tt>)</span>
+      
+      
+        <em class="default">(defaults to: <tt>&#39;6G&#39;</tt>)</em>
+      
+      
+        &mdash;
+        <div class='inline'>
+<p>hard memory ceiling</p>
+</div>
+      
+    </li>
+  
+    <li>
+      
+        <span class='name'>ps_high_mem</span>
+      
+      
+        <span class='type'>(<tt>String</tt>)</span>
+      
+      
+        <em class="default">(defaults to: <tt>&#39;5G&#39;</tt>)</em>
+      
+      
+        &mdash;
+        <div class='inline'>
+<p>soft limit to make kernel reclaim earlier</p>
+</div>
+      
+    </li>
+  
+    <li>
+      
+        <span class='name'>ps_swap_mem</span>
+      
+      
+        <span class='type'>(<tt>String</tt>)</span>
+      
+      
+        <em class="default">(defaults to: <tt>&#39;4G&#39;</tt>)</em>
+      
+      
+        &mdash;
+        <div class='inline'>
+<p>allow swap, but limit it</p>
+</div>
+      
+    </li>
+  
+    <li>
+      
+        <span class='name'>ps_oom_score</span>
+      
+      
+        <span class='type'>(<tt>String</tt>)</span>
+      
+      
+        <em class="default">(defaults to: <tt>&#39;500&#39;</tt>)</em>
+      
+      
+        &mdash;
+        <div class='inline'>
+<p>OOM killer choosing prometheus</p>
+</div>
+      
+    </li>
+  
+    <li>
+      
+        <span class='name'>ps_max_procs</span>
+      
+      
+        <span class='type'>(<tt>String</tt>)</span>
+      
+      
+        <em class="default">(defaults to: <tt>&#39;1&#39;</tt>)</em>
+      
+      
+        &mdash;
+        <div class='inline'>
+<p>reduce parallel WAL replay workers</p>
 </div>
       
     </li>
@@ -391,11 +481,6 @@
         <pre class="lines">
 
 
-21
-22
-23
-24
-25
 26
 27
 28
@@ -440,10 +525,22 @@
 67
 68
 69
-70</pre>
+70
+71
+72
+73
+74
+75
+76
+77
+78
+79
+80
+81
+82</pre>
       </td>
       <td>
-        <pre class="code"><span class="info file"># File 'manifests/params.pp', line 21</span>
+        <pre class="code"><span class="info file"># File 'manifests/params.pp', line 26</span>
 
 class prometheus_cd::params (
 
@@ -472,6 +569,13 @@ class prometheus_cd::params (
   String $ps_retention_size     = &#39;20GB&#39;,
   String $ps_wal_seg_size       = &#39;50MB&#39;,
 
+  # service
+  String $ps_max_mem            = &#39;6G&#39;,
+  String $ps_high_mem           = &#39;5G&#39;,
+  String $ps_swap_mem           = &#39;4G&#39;,
+  String $ps_oom_score          = &#39;500&#39;,
+  String $ps_max_procs          = &#39;1&#39;,
+
 ) {
   # defaults
   $fqdn                   = $facts[&#39;networking&#39;][&#39;fqdn&#39;]
diff --git a/manifests/params.pp b/manifests/params.pp
index bfcd81e..7d12ac8 100644
--- a/manifests/params.pp
+++ b/manifests/params.pp
@@ -17,6 +17,11 @@
 # @param [String] ps_retention_time tsdb retention time
 # @param [String] ps_retention_size tsdb retention size
 # @param [String] ps_wal_seg_size WAL segment size
+# @param [String] ps_max_mem hard memory ceiling
+# @param [String] ps_high_mem soft limit to make kernel reclaim earlier
+# @param [String] ps_swap_mem allow swap, but limit it
+# @param [String] ps_oom_score OOM killer choosing prometheus
+# @param [String] ps_max_procs  reduce parallel WAL replay workers
 ##############################################################################
 class prometheus_cd::params (
 
@@ -45,6 +50,13 @@ class prometheus_cd::params (
   String $ps_retention_size     = '20GB',
   String $ps_wal_seg_size       = '50MB',
 
+  # service
+  String $ps_max_mem            = '6G',
+  String $ps_high_mem           = '5G',
+  String $ps_swap_mem           = '4G',
+  String $ps_oom_score          = '500',
+  String $ps_max_procs          = '1',
+
 ) {
   # defaults
   $fqdn                   = $facts['networking']['fqdn']
diff --git a/templates/override.conf.erb b/templates/override.conf.erb
index 3d13498..99c2faf 100644
--- a/templates/override.conf.erb
+++ b/templates/override.conf.erb
@@ -2,6 +2,12 @@
 #####    File created by Puppet - manual changes will be overwritten      #####
 ###############################################################################
 [Service]
+MemoryMax=<%= @ps_max_mem %>
+MemoryHigh=<%= @ps_high_mem %>
+MemorySwapMax=<%= @ps_swap_mem %>
+OOMScoreAdjust=<%= @ps_oom_score %>
+Environment="GOMAXPROCS=<%= @ps_max_procs %>"
+
 ExecStart=
 ExecStart=/usr/bin/prometheus \
   --config.file=/etc/prometheus/prometheus.yml \