Instrument the database and WAL file size

1 files changed, 25 insertions, 0 deletions

diff --git a/nar-herder/database.scm b/nar-herder/database.scm
index 75cd049..2db561a 100644
--- a/nar-herder/database.scm
+++ b/nar-herder/database.scm
@@ -33,6 +33,7 @@
   #:use-module (guix derivations)
   #:use-module (nar-herder utils)
   #:export (setup-database
+            update-database-metrics!
 
             database-optimize
             database-spawn-fibers
@@ -384,6 +385,30 @@ CREATE TABLE scheduled_cached_narinfo_removal (
                    writer-thread-channel
                    metrics-registry)))
 
+(define (update-database-metrics! database)
+  (let* ((db-filename (database-file database))
+         (db-wal-filename
+          (string-append db-filename "-wal"))
+
+         (registry (database-metrics-registry database))
+         (db-bytes
+          (or (metrics-registry-fetch-metric registry
+                                             "database_bytes")
+              (make-gauge-metric
+               registry "database_bytes"
+               #:docstring "Size of the SQLite database file")))
+         (db-wal-bytes
+          (or (metrics-registry-fetch-metric registry
+                                             "database_wal_bytes")
+              (make-gauge-metric
+               registry "database_wal_bytes"
+               #:docstring "Size of the SQLite Write Ahead Log file"))))
+
+
+    (metric-set db-bytes (stat:size (stat db-filename)))
+    (metric-set db-wal-bytes (stat:size (stat db-wal-filename))))
+  #t)
+
 (define (db-optimize db db-filename)
   (define (wal-size)
     (let ((db-wal-filename