diff --git a/doc/source/admin/monitoring.rst b/doc/source/admin/monitoring.rst
index 6dbdb31..0fdb3b2 100644
--- a/doc/source/admin/monitoring.rst
+++ b/doc/source/admin/monitoring.rst
@@ -146,6 +146,12 @@
 
       The one-minute load average of this executor, multiplied by 100.
 
+   .. stat:: pct_available_ram
+      :type: gauge
+
+      The available RAM (including buffers and cache) on this
+      executor, as a percentage multiplied by 100.
+
 .. stat:: zuul.nodepool
 
    Holds metrics related to Zuul requests from Nodepool.
diff --git a/zuul/executor/server.py b/zuul/executor/server.py
index d2c04ac..6346e7c 100644
--- a/zuul/executor/server.py
+++ b/zuul/executor/server.py
@@ -1798,6 +1798,7 @@
         if self.statsd:
             base_key = 'zuul.executor.%s' % self.hostname
             self.statsd.gauge(base_key + '.load_average', 0)
+            self.statsd.gauge(base_key + '.pct_available_ram', 0)
             self.statsd.gauge(base_key + '.running_builds', 0)
 
         self.log.debug("Stopped")
@@ -1979,6 +1980,8 @@
             base_key = 'zuul.executor.%s' % self.hostname
             self.statsd.gauge(base_key + '.load_average',
                               int(load_avg * 100))
+            self.statsd.gauge(base_key + '.pct_available_ram',
+                              int(avail_mem_pct * 100))
             self.statsd.gauge(base_key + '.running_builds',
                               len(self.job_workers))