Add dbstat metrics

1 files changed, 53 insertions, 0 deletions

diff --git a/guix-build-coordinator/datastore/sqlite.scm b/guix-build-coordinator/datastore/sqlite.scm
index c3b62b2..215c07e 100644
--- a/guix-build-coordinator/datastore/sqlite.scm
+++ b/guix-build-coordinator/datastore/sqlite.scm
@@ -351,6 +351,59 @@ PRAGMA optimize;")
 
   (spawn-fiber
    (lambda ()
+     (let* ((registry
+             (slot-ref datastore 'metrics-registry))
+            (dbstat-metrics
+             (map
+              (lambda (name)
+                (let ((metric-name
+                       (string-append "datastore_dbstat_"
+                                      (symbol->string name))))
+                  (cons
+                   name
+                   (or (metrics-registry-fetch-metric registry
+                                                      metric-name)
+                       (make-gauge-metric registry metric-name
+                                          #:labels '(name))))))
+              '(pageno ncell payload unused mx_payload pgsize))))
+
+       (while #t
+         (with-exception-handler
+             (lambda (exn)
+               (simple-format
+                (current-error-port)
+                "exception fetching dbstat metrics: ~A\n" exn))
+           (lambda ()
+             (call-with-worker-thread
+              (slot-ref datastore 'worker-reader-thread-channel)
+              (lambda (db)
+                (let ((statement
+                       (sqlite-prepare
+                        db
+                        "
+SELECT * FROM dbstat WHERE aggregate = true"
+                        #:cache? #t))
+                      (dbstat-columns
+                       '(#f #f pageno #f ncell payload unused mx_payload #f pgsize)))
+                  (sqlite-fold
+                   (lambda (row _)
+                     (for-each
+                      (lambda (column val)
+                        (when column
+                          (metric-set (assq-ref dbstat-metrics column)
+                                      val
+                                      #:label-values
+                                      `((name . ,(vector-ref row 0))))))
+                      dbstat-columns
+                      (vector->list row)))
+                   #f
+                   statement)
+                  (sqlite-reset statement))))
+             (sleep (* 60 60 60)))
+           #:unwind? #t)))))
+
+  (spawn-fiber
+   (lambda ()
      (while #t
        (sleep (* 60 10))                ; 10 minutes
        (with-exception-handler