Remove invalid query ID cache from HBO cache manager

This cache adds a query ID when HBO failed to fetch history stats for
this query. Later during cost based planning, it will skip reading history
stats. However, the saving is small as the reading will be from cache.
And currently we run HBO optimizer twice, getting empty stats for one run
does not necessarily mean getting empty stats for the other run. This is
an over optimization and I remove it here.

presto-main/src/main/java/com/facebook/presto/cost/HistoryBasedPlanStatisticsCalculator.java

@@ -142,7 +142,7 @@ private Map<PlanCanonicalizationStrategy, PlanNodeWithHash> getPlanNodeHashes(Pl
 
     private PlanNodeStatsEstimate getStatistics(PlanNode planNode, Session session, Lookup lookup, PlanNodeStatsEstimate delegateStats)
     {
-        if (!useHistoryBasedPlanStatisticsEnabled(session) || historyBasedStatisticsCacheManager.loadHistoryFailed(session.getQueryId())) {
+        if (!useHistoryBasedPlanStatisticsEnabled(session)) {
             return delegateStats;
         }
 

presto-main/src/main/java/com/facebook/presto/cost/HistoryBasedStatisticsCacheManager.java

@@ -46,9 +46,6 @@ public class HistoryBasedStatisticsCacheManager
 
     private final Map<QueryId, Map<CachingPlanCanonicalInfoProvider.InputTableCacheKey, PlanStatistics>> inputTableStatistics = new ConcurrentHashMap<>();
 
-    // Whether the history is loaded successfully
-    private final Set<QueryId> invalidQueryId = ConcurrentHashMap.newKeySet();
-
     public HistoryBasedStatisticsCacheManager() {}
 
     public LoadingCache<PlanNodeWithHash, HistoricalPlanStatistics> getStatisticsCache(QueryId queryId, Supplier<HistoryBasedPlanStatisticsProvider> historyBasedPlanStatisticsProvider, long timeoutInMilliSeconds)
@@ -59,24 +56,13 @@ public LoadingCache<PlanNodeWithHash, HistoricalPlanStatistics> getStatisticsCac
                     @Override
                     public HistoricalPlanStatistics load(PlanNodeWithHash key)
                     {
-                        if (invalidQueryId.contains(queryId)) {
-                            return empty();
-                        }
                         return loadAll(Collections.singleton(key)).values().stream().findAny().orElseGet(HistoricalPlanStatistics::empty);
                     }
 
                     @Override
                     public Map<PlanNodeWithHash, HistoricalPlanStatistics> loadAll(Iterable<? extends PlanNodeWithHash> keys)
                     {
-                        if (invalidQueryId.contains(queryId)) {
-                            Map<PlanNodeWithHash, HistoricalPlanStatistics> emptyResult = new HashMap<>();
-                            keys.forEach(x -> emptyResult.put(x, empty()));
-                            return emptyResult;
-                        }
                         Map<PlanNodeWithHash, HistoricalPlanStatistics> statistics = new HashMap<>(historyBasedPlanStatisticsProvider.get().getStats(ImmutableList.copyOf(keys), timeoutInMilliSeconds));
-                        if (statistics.isEmpty()) {
-                            invalidQueryId.add(queryId);
-                        }
                         // loadAll excepts all keys to be written
                         for (PlanNodeWithHash key : keys) {
                             statistics.putIfAbsent(key, empty());
@@ -101,17 +87,11 @@ public void invalidate(QueryId queryId)
         statisticsCache.remove(queryId);
         canonicalInfoCache.remove(queryId);
         inputTableStatistics.remove(queryId);
-        invalidQueryId.remove(queryId);
     }
 
     @VisibleForTesting
     public Map<QueryId, Map<CachingPlanCanonicalInfoProvider.CacheKey, PlanNodeCanonicalInfo>> getCanonicalInfoCache()
     {
         return canonicalInfoCache;
     }
-
-    public boolean loadHistoryFailed(QueryId queryId)
-    {
-        return invalidQueryId.contains(queryId);
-    }
 }