ctdb-daemon: Add separate hot keys array for database statistics

There are 2 reasons for this.  Sorting of hot keys is broken and will
be changed to an implementation that needs a named (i.e. not
anonymous) structure.  Also, at least one non-protocol field will be
added to facilitate more useful logging.

Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Amitay Isaacs <amitay@gmail.com>

diff --git a/ctdb/include/ctdb_private.h b/ctdb/include/ctdb_private.h
index e532323bb34614df0a759ed7304d58e8b5c47e0b..3eb536672b2821e33fe97f31eb0aa2fa3b8a8b94 100644 (file)
--- a/ctdb/include/ctdb_private.h
+++ b/ctdb/include/ctdb_private.h
@@ -342,6 +342,11 @@ struct ctdb_context {
        struct lock_context *lock_pending;
 };
 
+struct ctdb_db_hot_key {
+       uint32_t count;
+       TDB_DATA key;
+};
+
 struct ctdb_db_context {
        struct ctdb_db_context *next, *prev;
        struct ctdb_context *ctdb;
@@ -375,6 +380,7 @@ struct ctdb_db_context {
        struct trbt_tree *defer_dmaster;
 
        struct ctdb_db_statistics_old statistics;
+       struct ctdb_db_hot_key hot_keys[MAX_HOT_KEYS];
 
        struct lock_context *lock_current;
        struct lock_context *lock_pending;

diff --git a/ctdb/server/ctdb_call.c b/ctdb/server/ctdb_call.c
index f8bf2d8d41efb56b9256b60f255a1f12c5952434..485b0b3bd32a9da921f980ee33367a454d0f3a14 100644 (file)
--- a/ctdb/server/ctdb_call.c
+++ b/ctdb/server/ctdb_call.c
@@ -828,23 +828,23 @@ ctdb_update_db_stat_hot_keys(struct ctdb_db_context *ctdb_db, TDB_DATA key,
        char *keystr;
 
        /* smallest value is always at index 0 */
-       if (count <= ctdb_db->statistics.hot_keys[0].count) {
+       if (count <= ctdb_db->hot_keys[0].count) {
                return;
        }
 
        /* see if we already know this key */
        for (i = 0; i < MAX_HOT_KEYS; i++) {
-               if (key.dsize != ctdb_db->statistics.hot_keys[i].key.dsize) {
+               if (key.dsize != ctdb_db->hot_keys[i].key.dsize) {
                        continue;
                }
-               if (memcmp(key.dptr, ctdb_db->statistics.hot_keys[i].key.dptr, key.dsize)) {
+               if (memcmp(key.dptr, ctdb_db->hot_keys[i].key.dptr, key.dsize)) {
                        continue;
                }
                /* found an entry for this key */
-               if (count <= ctdb_db->statistics.hot_keys[i].count) {
+               if (count <= ctdb_db->hot_keys[i].count) {
                        return;
                }
-               ctdb_db->statistics.hot_keys[i].count = count;
+               ctdb_db->hot_keys[i].count = count;
                goto sort_keys;
        }
 
@@ -855,12 +855,14 @@ ctdb_update_db_stat_hot_keys(struct ctdb_db_context *ctdb_db, TDB_DATA key,
                id = 0;
        }
 
-       if (ctdb_db->statistics.hot_keys[id].key.dptr != NULL) {
-               talloc_free(ctdb_db->statistics.hot_keys[id].key.dptr);
+       if (ctdb_db->hot_keys[id].key.dptr != NULL) {
+               talloc_free(ctdb_db->hot_keys[id].key.dptr);
        }
-       ctdb_db->statistics.hot_keys[id].key.dsize = key.dsize;
-       ctdb_db->statistics.hot_keys[id].key.dptr  = talloc_memdup(ctdb_db, key.dptr, key.dsize);
-       ctdb_db->statistics.hot_keys[id].count = count;
+       ctdb_db->hot_keys[id].key.dsize = key.dsize;
+       ctdb_db->hot_keys[id].key.dptr = talloc_memdup(ctdb_db,
+                                                      key.dptr,
+                                                      key.dsize);
+       ctdb_db->hot_keys[id].count = count;
 
        keystr = hex_encode_talloc(ctdb_db,
                                   (unsigned char *)key.dptr, key.dsize);
@@ -871,17 +873,17 @@ ctdb_update_db_stat_hot_keys(struct ctdb_db_context *ctdb_db, TDB_DATA key,
 
 sort_keys:
        for (i = 1; i < MAX_HOT_KEYS; i++) {
-               if (ctdb_db->statistics.hot_keys[i].count == 0) {
+               if (ctdb_db->hot_keys[i].count == 0) {
                        continue;
                }
-               if (ctdb_db->statistics.hot_keys[i].count < ctdb_db->statistics.hot_keys[0].count) {
-                       count = ctdb_db->statistics.hot_keys[i].count;
-                       ctdb_db->statistics.hot_keys[i].count = ctdb_db->statistics.hot_keys[0].count;
-                       ctdb_db->statistics.hot_keys[0].count = count;
-
-                       key = ctdb_db->statistics.hot_keys[i].key;
-                       ctdb_db->statistics.hot_keys[i].key = ctdb_db->statistics.hot_keys[0].key;
-                       ctdb_db->statistics.hot_keys[0].key = key;
+               if (ctdb_db->hot_keys[i].count < ctdb_db->hot_keys[0].count) {
+                       count = ctdb_db->hot_keys[i].count;
+                       ctdb_db->hot_keys[i].count = ctdb_db->hot_keys[0].count;
+                       ctdb_db->hot_keys[0].count = count;
+
+                       key = ctdb_db->hot_keys[i].key;
+                       ctdb_db->hot_keys[i].key = ctdb_db->hot_keys[0].key;
+                       ctdb_db->hot_keys[0].key = key;
                }
        }
 }

diff --git a/ctdb/server/ctdb_ltdb_server.c b/ctdb/server/ctdb_ltdb_server.c
index ce3569fe7b19f8dd6663fed9c8d53c2d548bca0a..4b14a6a2a167117e5770a3a37a572a0e977f8a8f 100644 (file)
--- a/ctdb/server/ctdb_ltdb_server.c
+++ b/ctdb/server/ctdb_ltdb_server.c
@@ -1597,13 +1597,14 @@ int ctdb_set_db_sticky(struct ctdb_context *ctdb, struct ctdb_db_context *ctdb_d
 
 void ctdb_db_statistics_reset(struct ctdb_db_context *ctdb_db)
 {
-       struct ctdb_db_statistics_old *s = &ctdb_db->statistics;
        int i;
 
        for (i=0; i<MAX_HOT_KEYS; i++) {
-               if (s->hot_keys[i].key.dsize > 0) {
-                       talloc_free(s->hot_keys[i].key.dptr);
+               if (ctdb_db->hot_keys[i].key.dsize > 0) {
+                       TALLOC_FREE(ctdb_db->hot_keys[i].key.dptr);
+                       ctdb_db->hot_keys[i].key.dsize = 0;
                }
+               ctdb_db->hot_keys[i].count = 0;
        }
 
        ZERO_STRUCT(ctdb_db->statistics);
@@ -1627,7 +1628,13 @@ int32_t ctdb_control_get_db_statistics(struct ctdb_context *ctdb,
 
        len = offsetof(struct ctdb_db_statistics_old, hot_keys_wire);
        for (i = 0; i < MAX_HOT_KEYS; i++) {
-               len += ctdb_db->statistics.hot_keys[i].key.dsize;
+               struct ctdb_db_statistics_old *s = &ctdb_db->statistics;
+
+               s->hot_keys[i].key.dsize = ctdb_db->hot_keys[i].key.dsize;
+               s->hot_keys[i].key.dptr = ctdb_db->hot_keys[i].key.dptr;
+               s->hot_keys[i].count = ctdb_db->hot_keys[i].count;
+
+               len += s->hot_keys[i].key.dsize;
        }
 
        stats = talloc_size(outdata, len);