Add KSTAT_TYPE_TXG type

Add a new kstat type for tracking useful statistics about a TXG.
The new KSTAT_TYPE_TXG type can be used to tracks the following
statistics per-txg.

  txg          - Unique txg number
  state        - State (O)pen/(Q)uiescing/(S)yncing/(C)ommitted
  birth;       - Creation time
  nread        - Bytes read
  nwritten;    - Bytes written
  reads        - IOPs read
  writes       - IOPs write
  open_time;   - Length in nanoseconds the txg was open
  quiesce_time - Length in nanoseconds the txg was quiescing
  sync_time;   - Length in nanoseconds the txg was syncing

Signed-off-by: Brian Behlendorf <[email protected]>

1 files changed, 22 insertions, 1 deletions

diff --git a/include/sys/kstat.h b/include/sys/kstat.h
index 45386d49a..06379f827 100644
--- a/include/sys/kstat.h
+++ b/include/sys/kstat.h
@@ -43,7 +43,8 @@
 #define KSTAT_TYPE_INTR         2       /* interrupt stats; ks_ndata == 1 */
 #define KSTAT_TYPE_IO           3       /* I/O stats; ks_ndata == 1 */
 #define KSTAT_TYPE_TIMER        4       /* event timer; ks_ndata >= 1 */
-#define KSTAT_NUM_TYPES         5
+#define KSTAT_TYPE_TXG          5       /* txg sync; ks_ndata >= 1 */
+#define KSTAT_NUM_TYPES         6
 
 #define KSTAT_DATA_CHAR         0
 #define KSTAT_DATA_INT32        1
@@ -156,6 +157,26 @@ typedef struct kstat_timer {
         hrtime_t     stop_time;            /* previous event stop time */
 } kstat_timer_t;
 
+typedef enum kstat_txg_state {
+        TXG_STATE_OPEN      = 1,
+        TXG_STATE_QUIESCING = 2,
+        TXG_STATE_SYNCING   = 3,
+        TXG_STATE_COMMITTED = 4,
+} kstat_txg_state_t;
+
+typedef struct kstat_txg {
+        u_longlong_t       txg;         /* txg id */
+        kstat_txg_state_t  state;       /* txg state */
+        hrtime_t           birth;       /* birth time stamp */
+        u_longlong_t       nread;       /* number of bytes read */
+        u_longlong_t       nwritten;    /* number of bytes written */
+        uint_t             reads;       /* number of read operations */
+        uint_t             writes;      /* number of write operations */
+        hrtime_t           open_time;   /* open time */
+        hrtime_t           quiesce_time;/* quiesce time */
+        hrtime_t           sync_time;   /* sync time */
+} kstat_txg_t;
+
 int spl_kstat_init(void);
 void spl_kstat_fini(void);