tdb2: hash chaining

[ccan] / ccan / tdb2 / summary.c

diff --git a/ccan/tdb2/summary.c b/ccan/tdb2/summary.c
index 42b1163e8b3fe25fc007e2b15d741fc0f5afa898..a03b048651ef9d15e910c4eae22a9caf4e824471 100644 (file)
--- a/ccan/tdb2/summary.c
+++ b/ccan/tdb2/summary.c
@@ -43,7 +43,8 @@ static bool summarize(struct tdb_context *tdb,
                      struct tally *data,
                      struct tally *extra,
                      struct tally *uncoal,
-                     struct tally *buckets)
+                     struct tally *buckets,
+                     struct tally *chains)
 {
        tdb_off_t off;
        tdb_len_t len;
@@ -83,7 +84,7 @@ static bool summarize(struct tdb_context *tdb,
                                + rec_extra_padding(&p->u);
 
                        /* FIXME: Use different magic for hashes, flists. */
-                       if (!rec_key_length(&p->u) && rec_hash(&p->u) < 2) {
+                       if (!rec_key_length(&p->u) && rec_hash(&p->u) < 3) {
                                if (rec_hash(&p->u) == 0) {
                                        int count = count_hash(tdb,
                                                        off + sizeof(p->u),
@@ -91,9 +92,11 @@ static bool summarize(struct tdb_context *tdb,
                                        if (count == -1)
                                                return false;
                                        tally_add(hashes, count);
-                               } else {
+                               } else if (rec_hash(&p->u) == 1) {
                                        tally_add(flists,
                                                  rec_data_length(&p->u));
+                               } else if (rec_hash(&p->u) == 2) {
+                                       tally_add(chains, 1);
                                }
                        } else {
                                tally_add(keys, rec_key_length(&p->u));
@@ -121,6 +124,7 @@ static bool summarize(struct tdb_context *tdb,
        "Smallest/average/largest uncoalesced runs: %zu/%zu/%zu\n%s" \
        "Number of free lists: %zu\n%s" \
        "Toplevel hash used: %u of %u\n" \
+       "Number of chains: %zu\n" \
        "Number of subhashes: %zu\n" \
        "Smallest/average/largest subhash entries: %zu/%zu/%zu\n%s" \
        "Percentage keys/data/padding/free/rechdrs/freehdrs/hashes: %.0f/%.0f/%.0f/%.0f/%.0f/%.0f/%.0f\n"
@@ -139,7 +143,7 @@ char *tdb_summary(struct tdb_context *tdb, enum tdb_summary_flags flags)
 {
        tdb_len_t len;
        struct tally *flists, *hashes, *freet, *keys, *data, *extra, *uncoal,
-               *buckets;
+               *buckets, *chains;
        char *hashesg, *freeg, *keysg, *datag, *extrag, *uncoalg, *bucketsg;
        char *ret = NULL;
 
@@ -162,15 +166,16 @@ char *tdb_summary(struct tdb_context *tdb, enum tdb_summary_flags flags)
        extra = tally_new(HISTO_HEIGHT);
        uncoal = tally_new(HISTO_HEIGHT);
        buckets = tally_new(HISTO_HEIGHT);
+       chains = tally_new(HISTO_HEIGHT);
        if (!flists || !hashes || !freet || !keys || !data || !extra
-           || !uncoal || !buckets) {
+           || !uncoal || !buckets || !chains) {
                tdb_logerr(tdb, TDB_ERR_OOM, TDB_DEBUG_ERROR,
                           "tdb_summary: failed to allocate tally structures");
                goto unlock;
        }
 
        if (!summarize(tdb, hashes, flists, freet, keys, data, extra, uncoal,
-                      buckets))
+                      buckets, chains))
                goto unlock;
 
        if (flags & TDB_SUMMARY_HISTOGRAMS) {
@@ -218,6 +223,7 @@ char *tdb_summary(struct tdb_context *tdb, enum tdb_summary_flags flags)
                      count_hash(tdb, offsetof(struct tdb_header, hashtable),
                                 TDB_TOPLEVEL_HASH_BITS),
                      1 << TDB_TOPLEVEL_HASH_BITS,
+                     tally_num(chains),
                      tally_num(hashes),
                      tally_min(hashes), tally_mean(hashes), tally_max(hashes),
                      hashesg ? hashesg : "",
@@ -231,7 +237,8 @@ char *tdb_summary(struct tdb_context *tdb, enum tdb_summary_flags flags)
                      * 100.0 / tdb->map_size,
                      (tally_num(hashes)
                       * (sizeof(tdb_off_t) << TDB_SUBLEVEL_HASH_BITS)
-                      + (sizeof(tdb_off_t) << TDB_TOPLEVEL_HASH_BITS))
+                      + (sizeof(tdb_off_t) << TDB_TOPLEVEL_HASH_BITS)
+                      + sizeof(struct tdb_chain) * tally_num(chains))
                      * 100.0 / tdb->map_size);
 
 unlock:
@@ -249,6 +256,7 @@ unlock:
        free(data);
        free(extra);
        free(uncoal);
+       free(chains);
 
        tdb_allrecord_unlock(tdb, F_RDLCK);
        tdb_unlock_expand(tdb, F_RDLCK);