Keep statistics on number of BIO_READ, BIO_WRITE, BIO_DELETE and BIO_FLUSH

requests as well as number of activemap updates.

Number of BIO_WRITEs and activemap updates are especially interesting, because
if those two are too close to each other, it means that your workload needs
bigger number of dirty extents. Activemap should be updated as rarely as
possible.

MFC after:	1 week

1 files changed, 11 insertions, 0 deletions

diff --git a/sbin/hastctl/hastctl.c b/sbin/hastctl/hastctl.c
index c4cd6a4..2f8a6eb 100644
--- a/sbin/hastctl/hastctl.c
+++ b/sbin/hastctl/hastctl.c
@@ -341,6 +341,17 @@ control_status(struct nv *nv)
 		printf("  dirty: %ju (%NB)\n",
 		    (uintmax_t)nv_get_uint64(nv, "dirty%u", ii),
 		    (intmax_t)nv_get_uint64(nv, "dirty%u", ii));
+		printf("  statistics:\n");
+		printf("    reads: %ju\n",
+		    (uint64_t)nv_get_uint64(nv, "stat_read%u", ii));
+		printf("    writes: %ju\n",
+		    (uint64_t)nv_get_uint64(nv, "stat_write%u", ii));
+		printf("    deletes: %ju\n",
+		    (uint64_t)nv_get_uint64(nv, "stat_delete%u", ii));
+		printf("    flushes: %ju\n",
+		    (uint64_t)nv_get_uint64(nv, "stat_flush%u", ii));
+		printf("    activemap updates: %ju\n",
+		    (uint64_t)nv_get_uint64(nv, "stat_activemap_update%u", ii));
 	}
 	return (ret);
 }