erts: Suppress failed ETS memory checks

due to the grow/shrink hysteresis of the meta tables

6 files changed, 110 insertions, 9 deletions

diff --git a/erts/emulator/beam/erl_bif_info.c b/erts/emulator/beam/erl_bif_info.c
index 3fb866733c..abf20a90e4 100644
--- a/erts/emulator/beam/erl_bif_info.c
+++ b/erts/emulator/beam/erl_bif_info.c
@@ -3547,6 +3547,10 @@ BIF_RETTYPE erts_debug_get_internal_state_1(BIF_ALIST_1)
 	    size_t words = (sizeof(DbTable) + sizeof(Uint) - 1)/sizeof(Uint);
 	    BIF_RET(make_small((Uint) words));
 	}
+        else if (ERTS_IS_ATOM_STR("DbTable_meta", BIF_ARG_1)) {
+            /* Used by ets_SUITE (stdlib) */
+            BIF_RET(erts_ets_get_meta_state(BIF_P));
+        }
 	else if (ERTS_IS_ATOM_STR("check_io_debug", BIF_ARG_1)) {
 	    /* Used by driver_SUITE (emulator) */
 	    Uint sz, *szp;
@@ -4280,6 +4284,10 @@ BIF_RETTYPE erts_debug_set_internal_state_2(BIF_ALIST_2)
             }
             BIF_RET(am_ok);
         }
+        else if (ERTS_IS_ATOM_STR("DbTable_meta", BIF_ARG_1)) {
+            /* Used by ets_SUITE (stdlib) */
+            BIF_RET(erts_ets_restore_meta_state(BIF_P, BIF_ARG_2));
+        }
     }
 
     BIF_ERROR(BIF_P, BADARG);
diff --git a/erts/emulator/beam/erl_db.c b/erts/emulator/beam/erl_db.c
index bad34211a5..df4e34511f 100644
--- a/erts/emulator/beam/erl_db.c
+++ b/erts/emulator/beam/erl_db.c
@@ -3978,6 +3978,36 @@ erts_ets_colliding_names(Process* p, Eterm name, Uint cnt)
     return list;
 }
 
+/*
+ * For testing only
+ * Retreive meta table size state
+ */
+Eterm erts_ets_get_meta_state(Process* p)
+{
+    Eterm* hp = HAlloc(p, 3);
+    return TUPLE2(hp,
+                  erts_ets_hash_get_memstate(p, &meta_pid_to_tab->hash),
+                  erts_ets_hash_get_memstate(p, &meta_pid_to_fixed_tab->hash));
+}
+/*
+ * For testing only
+ * Restore a previously retrieved meta table size state.
+ * We do this to suppress failed memory checks
+ * caused by the hysteresis of meta tables grow/shrink limits.
+ */
+Eterm erts_ets_restore_meta_state(Process* p, Eterm meta_state)
+{
+    Eterm* tv;
+    Eterm* hp;
+    if (!is_tuple_arity(meta_state, 2))
+        return am_badarg;
+
+    tv = tuple_val(meta_state);
+    hp = HAlloc(p, 3);
+    return TUPLE2(hp,
+                  erts_ets_hash_restore_memstate(&meta_pid_to_tab->hash, tv[1]),
+                  erts_ets_hash_restore_memstate(&meta_pid_to_fixed_tab->hash, tv[2]));
+}
 
 #ifdef HARDDEBUG   /* Here comes some debug functions */
 
diff --git a/erts/emulator/beam/erl_db.h b/erts/emulator/beam/erl_db.h
index 2f3c4a8e1b..f7eb3dc45c 100644
--- a/erts/emulator/beam/erl_db.h
+++ b/erts/emulator/beam/erl_db.h
@@ -90,6 +90,8 @@ extern Export ets_select_continue_exp;
 extern erts_smp_atomic_t erts_ets_misc_mem_size;
 
 Eterm erts_ets_colliding_names(Process*, Eterm name, Uint cnt);
+Eterm erts_ets_get_meta_state(Process* p);
+Eterm erts_ets_restore_meta_state(Process* p, Eterm target_state);
 
 Uint erts_db_get_max_tabs(void);
 
diff --git a/erts/emulator/beam/erl_db_hash.c b/erts/emulator/beam/erl_db_hash.c
index 1752ec5191..581b135233 100644
--- a/erts/emulator/beam/erl_db_hash.c
+++ b/erts/emulator/beam/erl_db_hash.c
@@ -2726,7 +2726,6 @@ static void shrink(DbTableHash* tb, int nactive)
     done_resizing(tb);
 }
 
-
 /* Search a list of tuples for a matching key */
 
 static HashDbTerm* search_list(DbTableHash* tb, Eterm key, 
@@ -2977,6 +2976,48 @@ void db_calc_stats_hash(DbTableHash* tb, DbHashStats* stats)
     stats->std_dev_expected = sqrt(stats->avg_chain_len * (1 - 1.0/NACTIVE(tb)));
     stats->kept_items = kept_items;
 }
+
+/* For testing only */
+Eterm erts_ets_hash_get_memstate(Process* p, DbTableHash* tb)
+{
+    Eterm seg_cnt;
+    while (!begin_resizing(tb))
+        /*spinn*/;
+
+    seg_cnt = make_small(SLOT_IX_TO_SEG_IX(tb->nslots));
+    done_resizing(tb);
+    return seg_cnt;
+}
+/* For testing only */
+Eterm erts_ets_hash_restore_memstate(DbTableHash* tb, Eterm memstate)
+{
+    int seg_cnt, target;
+    int nactive;
+
+    if (!is_small(memstate))
+        return make_small(__LINE__);
+
+    target = signed_val(memstate);
+    if (target < 1)
+        return make_small(__LINE__);
+    while (1) {
+        while (!begin_resizing(tb))
+            /*spin*/;
+        seg_cnt = SLOT_IX_TO_SEG_IX(tb->nslots);
+        nactive = NACTIVE(tb);
+        done_resizing(tb);
+
+        if (target == seg_cnt)
+            return am_ok;
+        if (IS_FIXED(tb))
+            return make_small(__LINE__);
+        if (target < seg_cnt)
+            shrink(tb, nactive);
+        else
+            grow(tb, nactive);
+    }
+}
+
 #ifdef HARDDEBUG
 
 void db_check_table_hash(DbTable *tbl)
diff --git a/erts/emulator/beam/erl_db_hash.h b/erts/emulator/beam/erl_db_hash.h
index 2d9b5e308a..e209037878 100644
--- a/erts/emulator/beam/erl_db_hash.h
+++ b/erts/emulator/beam/erl_db_hash.h
@@ -107,5 +107,7 @@ typedef struct {
 }DbHashStats;
 
 void db_calc_stats_hash(DbTableHash* tb, DbHashStats*);
+Eterm erts_ets_hash_get_memstate(Process*, DbTableHash* tb);
+Eterm erts_ets_hash_restore_memstate(DbTableHash* tb, Eterm memstate);
 
 #endif /* _DB_HASH_H */
diff --git a/lib/stdlib/test/ets_SUITE.erl b/lib/stdlib/test/ets_SUITE.erl
index 6835e745bc..ea555f9c39 100644
--- a/lib/stdlib/test/ets_SUITE.erl
+++ b/lib/stdlib/test/ets_SUITE.erl
@@ -218,7 +218,7 @@ memory_check_summary(_Config) ->
 	    receive {get_failed_memchecks, FailedMemchecks} -> ok end,
 	    io:format("Failed memchecks: ~p\n",[FailedMemchecks]),
 	    NoFailedMemchecks = length(FailedMemchecks),
-	    if NoFailedMemchecks > 3 ->
+	    if NoFailedMemchecks > 1 ->
 		    ct:fail("Too many failed (~p) memchecks", [NoFailedMemchecks]);
 	       true ->
 		    ok
@@ -5728,27 +5728,45 @@ etsmem() ->
 			   {Bl0+Bl,BlSz0+BlSz}
 		   end, {0,0}, CS)
 	 end},
-    {Mem,AllTabs}.
+    {Mem,AllTabs, erts_debug:get_internal_state('DbTable_meta')}.
 
-verify_etsmem({MemInfo,AllTabs}) ->
+verify_etsmem(EtsMem) ->
     wait_for_test_procs(),
+    verify_etsmem(EtsMem, false).
+
+verify_etsmem({MemInfo,AllTabs,MetaState}=EtsMem, Adjusted) ->
     case etsmem() of
-	{MemInfo,_} ->
+	{MemInfo,_,_} ->
 	    io:format("Ets mem info: ~p", [MemInfo]),
 	    case MemInfo of
 		{ErlMem,EtsAlloc} when ErlMem == notsup; EtsAlloc == undefined ->
 		    %% Use 'erl +Mea max' to do more complete memory leak testing.
 		    {comment,"Incomplete or no mem leak testing"};
 		_ ->
-		    ok
+		    case Adjusted of
+			true ->
+			    {comment, "Meta state adjusted"};
+			false ->
+			    ok
+		    end
 	    end;
-	{MemInfo2, AllTabs2} ->
+
+	{MemInfo2, AllTabs2, MetaState2} ->
 	    io:format("Expected: ~p", [MemInfo]),
 	    io:format("Actual:   ~p", [MemInfo2]),
 	    io:format("Changed tables before: ~p\n",[AllTabs -- AllTabs2]),
 	    io:format("Changed tables after: ~p\n", [AllTabs2 -- AllTabs]),
-	    ets_test_spawn_logger ! {failed_memcheck, get('__ETS_TEST_CASE__')},
-	    {comment, "Failed memory check"}
+	    io:format("Meta state before: ~p\n", [MetaState]),
+	    io:format("Meta state after:  ~p\n", [MetaState2]),
+	    case {MetaState =:= MetaState2, Adjusted} of
+		{false, false} ->
+		    io:format("Adjust meta state and retry...\n\n",[]),
+		    {ok,ok} = erts_debug:set_internal_state('DbTable_meta', MetaState),
+		    verify_etsmem(EtsMem, true);
+		_ ->
+		    ets_test_spawn_logger ! {failed_memcheck, get('__ETS_TEST_CASE__')},
+		    {comment, "Failed memory check"}
+	    end
     end.