Add get-gc-metrics-updater

prometheus.scm

@@ -44,7 +44,9 @@
             metric-set
             metric-observe
 
-            call-with-duration-metric))
+            call-with-duration-metric
+
+            get-gc-metrics-updater))
 
 (define-record-type <metrics-registry>
   (make-metrics-registry-record metrics-hash namespace)
@@ -558,3 +560,28 @@ This procedure takes care of atomically replacing the file."
       (lambda (key . args)
         (false-if-exception (delete-file template))))))
 
+(define (get-gc-metrics-updater registry)
+  (define metrics
+    `((gc-time-taken
+       . ,(make-gauge-metric registry "guile_gc_time_taken"))
+      (heap-size
+       . ,(make-gauge-metric registry "guile_heap_size"))
+      (heap-free-size
+       . ,(make-gauge-metric registry "guile_heap_free_size"))
+      (heap-total-allocated
+       . ,(make-gauge-metric registry "guile_heap_total_allocated"))
+      (heap-allocated-since-gc
+       . ,(make-gauge-metric registry "guile_allocated_since_gc"))
+      (protected-objects
+       . ,(make-gauge-metric registry "guile_gc_protected_objects"))
+      (gc-times
+       . ,(make-gauge-metric registry "guile_gc_times"))))
+
+  (lambda ()
+    (let ((stats (gc-stats)))
+      (for-each
+       (match-lambda
+         ((name . metric)
+          (let ((value (assq-ref stats name)))
+            (metric-set metric value))))
+       metrics))))