time res

Signed-off-by: George Amanakis <[email protected]>
gamanakis · Aug 29, 2023 · 2b7322f · 2b7322f
1 parent 0b5dacd
commit 2b7322f
Showing 1 changed file with 12 additions and 0 deletions.
diff --git a/module/zfs/arc.c b/module/zfs/arc.c
@@ -9172,6 +9172,14 @@ l2arc_write_buffers(spa_t *spa, l2arc_dev_t *dev, uint64_t target_sz)
 		headroom = (headroom * l2arc_headroom_boost) / 100;
 
 	uint64_t i = 0;
+#ifdef _KERNEL
+	/*
+	 * Sweeping the full buf cache takes about 1.5-3 secs on a machine
+	 * with 8Gb RAM.
+	 */
+	hrtime_t start, end;
+	start = gethrtime();
+#endif
 	for (i = 0; ;i++) {
 		kmutex_t *hash_lock;
 		abd_t *to_write = NULL;
@@ -9344,6 +9352,10 @@ l2arc_write_buffers(spa_t *spa, l2arc_dev_t *dev, uint64_t target_sz)
 
 		zio_nowait(wzio);
 	}
+#ifdef _KERNEL
+	end = gethrtime();
+	cmn_err(CE_NOTE, "time: %llu", end-start);
+#endif
 
 	/* No buffers selected for writing? */
 	if (pio == NULL) {