diff options
Diffstat (limited to 'erts/emulator/beam/erl_db_hash.c')
-rw-r--r-- | erts/emulator/beam/erl_db_hash.c | 318 |
1 files changed, 231 insertions, 87 deletions
diff --git a/erts/emulator/beam/erl_db_hash.c b/erts/emulator/beam/erl_db_hash.c index 06dac8f161..dce0a3d621 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; @@ -684,6 +670,8 @@ int db_create_hash(Process *p, DbTable *tbl) int i; if (tb->common.type & DB_FREQ_READ) rwmtx_opt.type = ERTS_SMP_RWMTX_TYPE_FREQUENT_READ; + if (erts_ets_rwmtx_spin_count >= 0) + rwmtx_opt.main_spincount = erts_ets_rwmtx_spin_count; tb->locks = (DbTableHashFineLocks*) erts_db_alloc_fnf(ERTS_ALC_T_DB_SEG, /* Other type maybe? */ (DbTable *) tb, sizeof(DbTableHashFineLocks)); @@ -879,34 +867,49 @@ 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: @@ -1048,7 +1051,6 @@ static int db_get_element_hash(Process *p, DbTable *tbl, Eterm copy = db_copy_element_from_ets(&tb->common, p, &b->dbterm, ndex, &hp, 2); elem_list = CONS(hp, copy, elem_list); - hp += 2; } b = b->next; } @@ -1240,7 +1242,7 @@ 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 +2071,46 @@ 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 +2146,38 @@ 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); @@ -2402,10 +2472,10 @@ static int alloc_seg(DbTableHash *tb) */ static int free_seg(DbTableHash *tb, int free_records) { - int seg_ix = (tb->nslots >> SEGSZ_EXP) - 1; + const int seg_ix = (tb->nslots >> SEGSZ_EXP) - 1; + struct segment** const segtab = SEGTAB(tb); + struct ext_segment* const top = (struct ext_segment*) segtab[seg_ix]; int bytes; - struct segment** segtab = SEGTAB(tb); - struct ext_segment* top = (struct ext_segment*) segtab[seg_ix]; int nrecords = 0; ASSERT(top != NULL); @@ -2468,7 +2538,7 @@ static int free_seg(DbTableHash *tb, int free_records) (void*)top, bytes); #ifdef DEBUG if (seg_ix > 0) { - if (seg_ix < tb->nsegs) SEGTAB(tb)[seg_ix] = NULL; + segtab[seg_ix] = NULL; } else { SET_SEGTAB(tb, NULL); } @@ -2483,23 +2553,23 @@ 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 +2800,129 @@ 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 +2973,7 @@ 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 +2985,8 @@ 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 +2998,8 @@ 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 |