fix targeting on newer nodes, increase test stability

src/miner.erl

@@ -601,27 +601,28 @@ set_next_block_timer(State=#state{blockchain=Chain, start_block_time=StartBlockT
 
     StartHeight0 = application:get_env(miner, stabilization_period, 0),
     StartHeight = max(1, Height - StartHeight0),
-    StartBlockTime = case StartBlockTime0 of
-                         undefined ->
-                             case Height > StartHeight of
-                                 true ->
-                                     case blockchain:find_first_block_after(StartHeight, Chain) of
-                                         {ok, _, StartBlock} ->
-                                             blockchain_block:time(StartBlock);
-                                         _ ->
-                                             undefined
-                                     end;
-                                 false ->
-                                     undefined
-                             end;
-                         Time ->
-                             Time
-                     end,
+    {ActualStartHeight, StartBlockTime} =
+        case StartBlockTime0 of
+            undefined ->
+                case Height > StartHeight of
+                    true ->
+                        case blockchain:find_first_block_after(StartHeight, Chain) of
+                            {ok, Actual, StartBlock} ->
+                                {Actual, blockchain_block:time(StartBlock)};
+                            _ ->
+                                {0, undefined}
+                        end;
+                    false ->
+                        {0, undefined}
+                end;
+            Time ->
+                {StartHeight, Time}
+        end,
     AvgBlockTime = case StartBlockTime of
                        undefined ->
                            BlockTime;
                        _ ->
-                           (LastBlockTimestamp - StartBlockTime) / (Height - StartHeight)
+                           (LastBlockTimestamp - StartBlockTime) / (Height - ActualStartHeight)
                    end,
     BlockTimeDeviation0 = BlockTime - AvgBlockTime,
     lager:info("average ~p block times ~p difference ~p", [Height, AvgBlockTime, BlockTime - AvgBlockTime]),

test/miner_blockchain_SUITE.erl

@@ -105,6 +105,12 @@ init_per_testcase(TestCase, Config0) ->
     true = lists:all(fun(Res) -> Res == ok end, DKGResults),
 
     %% Get both consensus and non consensus miners
+    true = miner_ct_utils:wait_until(
+             fun() ->
+                     {_ConsensusMiners, NCMiners} = miner_ct_utils:miners_by_consensus_state(Miners),
+                     length(NCMiners) == 1
+             end, 25, 200),
+
     {ConsensusMiners, NonConsensusMiners} = miner_ct_utils:miners_by_consensus_state(Miners),
     ct:pal("ConsensusMiners: ~p, NonConsensusMiners: ~p", [ConsensusMiners, NonConsensusMiners]),
 
@@ -790,9 +796,18 @@ snapshot_test(Config) ->
 
     miner_ct_utils:start_miners([{Target, NewTargetEnv}]),
 
-    timer:sleep(5000),
+    miner_ct_utils:wait_until(
+      fun() ->
+              try
+                  undefined =/= ct_rpc:call(Target, blockchain_worker, blockchain, [])
+              catch _:_ ->
+                       false
+              end
+      end, 50, 200),
+
     ok = ct_rpc:call(Target, blockchain, reset_ledger_to_snap, []),
 
+
     ok = miner_ct_utils:wait_for_gte(height, Miners0, 25, all, 20),
     ok.