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-rw-r--r--erts/emulator/beam/erl_db_hash.c307
1 files changed, 225 insertions, 82 deletions
diff --git a/erts/emulator/beam/erl_db_hash.c b/erts/emulator/beam/erl_db_hash.c
index b1d9eb84bc..383ee7c430 100644
--- a/erts/emulator/beam/erl_db_hash.c
+++ b/erts/emulator/beam/erl_db_hash.c
@@ -174,7 +174,7 @@ static ERTS_INLINE void add_fixed_deletion(DbTableHash* tb, int ix)
/* optimised version of make_hash (normal case? atomic key) */
#define MAKE_HASH(term) \
((is_atom(term) ? (atom_tab(atom_val(term))->slot.bucket.hvalue) : \
- make_hash2(term)) % MAX_HASH)
+ make_internal_hash(term)) % MAX_HASH)
#ifdef ERTS_SMP
# define DB_HASH_LOCK_MASK (DB_HASH_LOCK_CNT-1)
@@ -382,7 +382,7 @@ static HashDbTerm* search_list(DbTableHash* tb, Eterm key,
static void shrink(DbTableHash* tb, int nactive);
static void grow(DbTableHash* tb, int nactive);
static Eterm build_term_list(Process* p, HashDbTerm* ptr1, HashDbTerm* ptr2,
- DbTableHash*);
+ Uint sz, DbTableHash*);
static int analyze_pattern(DbTableHash *tb, Eterm pattern,
struct mp_info *mpi);
@@ -426,6 +426,7 @@ static int db_select_count_continue_hash(Process *p, DbTable *tbl,
static int db_select_delete_continue_hash(Process *p, DbTable *tbl,
Eterm continuation, Eterm *ret);
+static int db_take_hash(Process *, DbTable *, Eterm, Eterm *);
static void db_print_hash(int to,
void *to_arg,
int show,
@@ -443,8 +444,11 @@ static int db_delete_all_objects_hash(Process* p, DbTable* tbl);
#ifdef HARDDEBUG
static void db_check_table_hash(DbTableHash *tb);
#endif
-static int db_lookup_dbterm_hash(DbTable *tbl, Eterm key, DbUpdateHandle* handle);
-static void db_finalize_dbterm_hash(DbUpdateHandle* handle);
+static int
+db_lookup_dbterm_hash(Process *p, DbTable *tbl, Eterm key, Eterm obj,
+ DbUpdateHandle* handle);
+static void
+db_finalize_dbterm_hash(int cret, DbUpdateHandle* handle);
static ERTS_INLINE void try_shrink(DbTableHash* tb)
{
@@ -536,6 +540,7 @@ DbTableMethod db_hash =
db_select_delete_continue_hash,
db_select_count_hash,
db_select_count_continue_hash,
+ db_take_hash,
db_delete_all_objects_hash,
db_free_table_hash,
db_free_table_continue_hash,
@@ -646,25 +651,6 @@ restart:
/* ToDo: Maybe try grow/shrink the table as well */
}
-/* Only used by tests
-*/
-Uint db_kept_items_hash(DbTableHash *tb)
-{
- Uint kept_items = 0;
- Uint ix = 0;
- erts_smp_rwmtx_t* lck = RLOCK_HASH(tb,ix);
- HashDbTerm* b;
- do {
- for (b = BUCKET(tb, ix); b != NULL; b = b->next) {
- if (b->hvalue == INVALID_HASH) {
- ++kept_items;
- }
- }
- ix = next_slot(tb, ix, &lck);
- }while (ix);
- return kept_items;
-}
-
int db_create_hash(Process *p, DbTable *tbl)
{
DbTableHash *tb = &tbl->hash;
@@ -879,34 +865,49 @@ Ldone:
return ret;
}
+static Eterm
+get_term_list(Process *p, DbTableHash *tb, Eterm key, HashValue hval,
+ HashDbTerm *b1, HashDbTerm **bend)
+{
+ HashDbTerm* b2 = b1->next;
+ Eterm copy;
+ Uint sz = b1->dbterm.size + 2;
+
+ if (tb->common.status & (DB_BAG | DB_DUPLICATE_BAG)) {
+ while (b2 && has_key(tb, b2, key, hval)) {
+ if (b2->hvalue != INVALID_HASH)
+ sz += b2->dbterm.size + 2;
+
+ b2 = b2->next;
+ }
+ }
+ copy = build_term_list(p, b1, b2, sz, tb);
+ CHECK_TABLES();
+ if (bend) {
+ *bend = b2;
+ }
+ return copy;
+}
+
int db_get_hash(Process *p, DbTable *tbl, Eterm key, Eterm *ret)
{
DbTableHash *tb = &tbl->hash;
HashValue hval;
int ix;
- HashDbTerm* b1;
+ HashDbTerm* b;
erts_smp_rwmtx_t* lck;
hval = MAKE_HASH(key);
lck = RLOCK_HASH(tb,hval);
ix = hash_to_ix(tb, hval);
- b1 = BUCKET(tb, ix);
-
- while(b1 != 0) {
- if (has_live_key(tb,b1,key,hval)) {
- HashDbTerm* b2 = b1->next;
- Eterm copy;
+ b = BUCKET(tb, ix);
- if (tb->common.status & (DB_BAG | DB_DUPLICATE_BAG)) {
- while(b2 != NULL && has_key(tb,b2,key,hval))
- b2 = b2->next;
- }
- copy = build_term_list(p, b1, b2, tb);
- CHECK_TABLES();
- *ret = copy;
+ while(b != 0) {
+ if (has_live_key(tb, b, key, hval)) {
+ *ret = get_term_list(p, tb, key, hval, b, NULL);
goto done;
}
- b1 = b1->next;
+ b = b->next;
}
*ret = NIL;
done:
@@ -1240,7 +1241,7 @@ static int db_slot_hash(Process *p, DbTable *tbl, Eterm slot_term, Eterm *ret)
lck = RLOCK_HASH(tb, slot);
nactive = NACTIVE(tb);
if (slot < nactive) {
- *ret = build_term_list(p, BUCKET(tb, slot), 0, tb);
+ *ret = build_term_list(p, BUCKET(tb, slot), NULL, 0, tb);
retval = DB_ERROR_NONE;
}
else if (slot == nactive) {
@@ -2069,6 +2070,46 @@ trap:
}
+static int db_take_hash(Process *p, DbTable *tbl, Eterm key, Eterm *ret)
+{
+ DbTableHash *tb = &tbl->hash;
+ HashDbTerm **bp, *b;
+ HashValue hval = MAKE_HASH(key);
+ erts_smp_rwmtx_t *lck = WLOCK_HASH(tb, hval);
+ int ix = hash_to_ix(tb, hval);
+ int nitems_diff = 0;
+
+ *ret = NIL;
+ for (bp = &BUCKET(tb, ix), b = *bp; b; bp = &b->next, b = b->next) {
+ if (has_live_key(tb, b, key, hval)) {
+ HashDbTerm *bend;
+
+ *ret = get_term_list(p, tb, key, hval, b, &bend);
+ while (b != bend) {
+ --nitems_diff;
+ if (nitems_diff == -1 && IS_FIXED(tb)) {
+ /* Pseudo remove (no need to keep several of same key) */
+ add_fixed_deletion(tb, ix);
+ bp = &b->next;
+ b->hvalue = INVALID_HASH;
+ b = b->next;
+ } else {
+ *bp = b->next;
+ free_term(tb, b);
+ b = *bp;
+ }
+ }
+ break;
+ }
+ }
+ WUNLOCK_HASH(lck);
+ if (nitems_diff) {
+ erts_smp_atomic_add_nob(&tb->common.nitems, nitems_diff);
+ try_shrink(tb);
+ }
+ return DB_ERROR_NONE;
+}
+
/*
** Other interface routines (not directly coupled to one bif)
*/
@@ -2104,10 +2145,38 @@ int db_mark_all_deleted_hash(DbTable *tbl)
static void db_print_hash(int to, void *to_arg, int show, DbTable *tbl)
{
DbTableHash *tb = &tbl->hash;
+ DbHashStats stats;
int i;
erts_print(to, to_arg, "Buckets: %d\n", NACTIVE(tb));
-
+
+#ifdef ERTS_SMP
+ i = tbl->common.is_thread_safe;
+ /* If crash dumping we set table to thread safe in order to
+ avoid taking any locks */
+ if (ERTS_IS_CRASH_DUMPING)
+ tbl->common.is_thread_safe = 1;
+
+ db_calc_stats_hash(&tbl->hash, &stats);
+
+ tbl->common.is_thread_safe = i;
+#else
+ db_calc_stats_hash(&tbl->hash, &stats);
+#endif
+
+ erts_print(to, to_arg, "Chain Length Avg: %f\n", stats.avg_chain_len);
+ erts_print(to, to_arg, "Chain Length Max: %d\n", stats.max_chain_len);
+ erts_print(to, to_arg, "Chain Length Min: %d\n", stats.min_chain_len);
+ erts_print(to, to_arg, "Chain Length Std Dev: %f\n",
+ stats.std_dev_chain_len);
+ erts_print(to, to_arg, "Chain Length Expected Std Dev: %f\n",
+ stats.std_dev_expected);
+
+ if (IS_FIXED(tb))
+ erts_print(to, to_arg, "Fixed: %d\n", stats.kept_items);
+ else
+ erts_print(to, to_arg, "Fixed: false\n");
+
if (show) {
for (i = 0; i < NACTIVE(tb); i++) {
HashDbTerm* list = BUCKET(tb,i);
@@ -2483,23 +2552,23 @@ static int free_seg(DbTableHash *tb, int free_records)
** Copy terms from ptr1 until ptr2
** works for ptr1 == ptr2 == 0 => []
** or ptr2 == 0
+** sz is either precalculated heap size or 0 if not known
*/
static Eterm build_term_list(Process* p, HashDbTerm* ptr1, HashDbTerm* ptr2,
- DbTableHash* tb)
+ Uint sz, DbTableHash* tb)
{
- int sz = 0;
HashDbTerm* ptr;
Eterm list = NIL;
Eterm copy;
Eterm *hp, *hend;
- ptr = ptr1;
- while(ptr != ptr2) {
-
- if (ptr->hvalue != INVALID_HASH)
- sz += ptr->dbterm.size + 2;
-
- ptr = ptr->next;
+ if (!sz) {
+ ptr = ptr1;
+ while(ptr != ptr2) {
+ if (ptr->hvalue != INVALID_HASH)
+ sz += ptr->dbterm.size + 2;
+ ptr = ptr->next;
+ }
}
hp = HAlloc(p, sz);
@@ -2730,59 +2799,129 @@ static HashDbTerm* next(DbTableHash *tb, Uint *iptr, erts_smp_rwmtx_t** lck_ptr,
return NULL;
}
-static int db_lookup_dbterm_hash(DbTable *tbl, Eterm key, DbUpdateHandle* handle)
+static int
+db_lookup_dbterm_hash(Process *p, DbTable *tbl, Eterm key, Eterm obj,
+ DbUpdateHandle* handle)
{
DbTableHash *tb = &tbl->hash;
- HashDbTerm* b;
- HashDbTerm** prevp;
- int ix;
HashValue hval;
+ HashDbTerm **bp, *b;
erts_smp_rwmtx_t* lck;
+ int flags = 0;
+
+ ASSERT(tb->common.status & DB_SET);
hval = MAKE_HASH(key);
- lck = WLOCK_HASH(tb,hval);
- ix = hash_to_ix(tb, hval);
- prevp = &BUCKET(tb, ix);
- b = *prevp;
+ lck = WLOCK_HASH(tb, hval);
+ bp = &BUCKET(tb, hash_to_ix(tb, hval));
+ b = *bp;
- while (b != 0) {
- if (has_live_key(tb,b,key,hval)) {
- handle->tb = tbl;
- handle->bp = (void**) prevp;
- handle->dbterm = &b->dbterm;
- handle->mustResize = 0;
- handle->new_size = b->dbterm.size;
- #if HALFWORD_HEAP
- handle->abs_vec = NULL;
- #endif
- handle->lck = lck;
- /* KEEP hval WLOCKED, db_finalize_dbterm_hash will WUNLOCK */
- return 1;
- }
- prevp = &b->next;
- b = *prevp;
+ for (;;) {
+ if (b == NULL) {
+ break;
+ }
+ if (has_key(tb, b, key, hval)) {
+ if (b->hvalue != INVALID_HASH) {
+ goto Ldone;
+ }
+ break;
+ }
+ bp = &b->next;
+ b = *bp;
}
- WUNLOCK_HASH(lck);
- return 0;
+
+ if (obj == THE_NON_VALUE) {
+ WUNLOCK_HASH(lck);
+ return 0;
+ }
+
+ {
+ Eterm *objp = tuple_val(obj);
+ int arity = arityval(*objp);
+ Eterm *htop, *hend;
+
+ ASSERT(arity >= tb->common.keypos);
+ htop = HAlloc(p, arity + 1);
+ hend = htop + arity + 1;
+ sys_memcpy(htop, objp, sizeof(Eterm) * (arity + 1));
+ htop[tb->common.keypos] = key;
+ obj = make_tuple(htop);
+
+ if (b == NULL) {
+ HashDbTerm *q = new_dbterm(tb, obj);
+
+ q->hvalue = hval;
+ q->next = NULL;
+ *bp = b = q;
+
+ {
+ int nitems = erts_smp_atomic_inc_read_nob(&tb->common.nitems);
+ int nactive = NACTIVE(tb);
+
+ if (nitems > nactive * (CHAIN_LEN + 1) && !IS_FIXED(tb)) {
+ grow(tb, nactive);
+ }
+ }
+ } else {
+ HashDbTerm *q, *next = b->next;
+
+ ASSERT(b->hvalue == INVALID_HASH);
+ q = replace_dbterm(tb, b, obj);
+ q->next = next;
+ q->hvalue = hval;
+ *bp = b = q;
+ erts_smp_atomic_inc_nob(&tb->common.nitems);
+ }
+
+ HRelease(p, hend, htop);
+ flags |= DB_NEW_OBJECT;
+ }
+
+Ldone:
+ handle->tb = tbl;
+ handle->bp = (void **)bp;
+ handle->dbterm = &b->dbterm;
+ handle->flags = flags;
+ handle->new_size = b->dbterm.size;
+#if HALFWORD_HEAP
+ handle->abs_vec = NULL;
+#endif
+ handle->lck = lck;
+ return 1;
}
/* Must be called after call to db_lookup_dbterm
*/
-static void db_finalize_dbterm_hash(DbUpdateHandle* handle)
+static void
+db_finalize_dbterm_hash(int cret, DbUpdateHandle* handle)
{
DbTable* tbl = handle->tb;
- HashDbTerm* oldp = (HashDbTerm*) *(handle->bp);
+ DbTableHash *tb = &tbl->hash;
+ HashDbTerm **bp = (HashDbTerm **) handle->bp;
+ HashDbTerm *b = *bp;
erts_smp_rwmtx_t* lck = (erts_smp_rwmtx_t*) handle->lck;
- ERTS_SMP_LC_ASSERT(IS_HASH_WLOCKED(&tbl->hash,lck)); /* locked by db_lookup_dbterm_hash */
+ ERTS_SMP_LC_ASSERT(IS_HASH_WLOCKED(tb, lck)); /* locked by db_lookup_dbterm_hash */
- ASSERT((&oldp->dbterm == handle->dbterm) == !(tbl->common.compress && handle->mustResize));
+ ASSERT((&b->dbterm == handle->dbterm) == !(tb->common.compress && handle->flags & DB_MUST_RESIZE));
+
+ if (handle->flags & DB_NEW_OBJECT && cret != DB_ERROR_NONE) {
+ if (IS_FIXED(tb)) {
+ add_fixed_deletion(tb, hash_to_ix(tb, b->hvalue));
+ b->hvalue = INVALID_HASH;
+ } else {
+ *bp = b->next;
+ free_term(tb, b);
+ }
- if (handle->mustResize) {
+ WUNLOCK_HASH(lck);
+ erts_smp_atomic_dec_nob(&tb->common.nitems);
+ try_shrink(tb);
+ } else if (handle->flags & DB_MUST_RESIZE) {
db_finalize_resize(handle, offsetof(HashDbTerm,dbterm));
WUNLOCK_HASH(lck);
- free_term(&tbl->hash, oldp);
+ free_term(tb, b);
}
else {
WUNLOCK_HASH(lck);
@@ -2833,6 +2972,7 @@ void db_calc_stats_hash(DbTableHash* tb, DbHashStats* stats)
erts_smp_rwmtx_t* lck;
int sum = 0;
int sq_sum = 0;
+ int kept_items = 0;
int ix;
int len;
@@ -2844,6 +2984,8 @@ void db_calc_stats_hash(DbTableHash* tb, DbHashStats* stats)
len = 0;
for (b = BUCKET(tb,ix); b!=NULL; b=b->next) {
len++;
+ if (b->hvalue == INVALID_HASH)
+ ++kept_items;
}
sum += len;
sq_sum += len*len;
@@ -2855,7 +2997,8 @@ void db_calc_stats_hash(DbTableHash* tb, DbHashStats* stats)
stats->std_dev_chain_len = sqrt((sq_sum - stats->avg_chain_len*sum) / NACTIVE(tb));
/* Expected standard deviation from a good uniform hash function,
ie binomial distribution (not taking the linear hashing into acount) */
- stats->std_dev_expected = sqrt(stats->avg_chain_len * (1 - 1.0/NACTIVE(tb)));
+ stats->std_dev_expected = sqrt(stats->avg_chain_len * (1 - 1.0/NACTIVE(tb)));
+ stats->kept_items = kept_items;
}
#ifdef HARDDEBUG