OP#179 add service control units for memory consumption

.gitignore

@@ -2,3 +2,4 @@
 Gemfile.lock
 FileList
 .scannerwork
+.vscode

.vscode/settings.json

@@ -1,6 +1,8 @@
 {
     "cSpell.words": [
         "changeme",
+        "GOMAXPROCS",
+        "procs",
         "reqpackage",
         "rpms",
         "sslcacert",

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']

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 \