Merge branch 'stable-3.1' into stable-3.2

* stable-3.1:
  Allow async receive-commits to have a thread-local cache
  Fix RepoRefCache stale checks during NoteDb rebuild
  Lazy load change notes when submit by push

Change-Id: Idb781e53343f98c898ecd4cd1033160b4ce4dfae
Release-Notes: skip

2 files changed, 15 insertions, 10 deletions

diff --git a/java/com/google/gerrit/server/git/receive/AsyncReceiveCommits.java b/java/com/google/gerrit/server/git/receive/AsyncReceiveCommits.java
index fc80490ae6..64a7cae22a 100644
--- a/java/com/google/gerrit/server/git/receive/AsyncReceiveCommits.java
+++ b/java/com/google/gerrit/server/git/receive/AsyncReceiveCommits.java
@@ -36,6 +36,7 @@ import com.google.gerrit.metrics.MetricMaker;
 import com.google.gerrit.metrics.Timer1;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.PublishCommentsOp;
+import com.google.gerrit.server.cache.PerThreadCache;
 import com.google.gerrit.server.config.AllUsersName;
 import com.google.gerrit.server.config.ConfigUtil;
 import com.google.gerrit.server.config.GerritServerConfig;
@@ -366,7 +367,7 @@ public class AsyncReceiveCommits {
         () -> {
           String oldName = Thread.currentThread().getName();
           Thread.currentThread().setName(oldName + "-for-" + currentThreadName);
-          try {
+          try (PerThreadCache threadLocalCache = PerThreadCache.create()) {
             return receiveCommits.processCommands(commands, monitor);
           } finally {
             Thread.currentThread().setName(oldName);
diff --git a/java/com/google/gerrit/server/git/receive/ReceiveCommits.java b/java/com/google/gerrit/server/git/receive/ReceiveCommits.java
index f0a9652ce0..171b6ad07f 100644
--- a/java/com/google/gerrit/server/git/receive/ReceiveCommits.java
+++ b/java/com/google/gerrit/server/git/receive/ReceiveCommits.java
@@ -3260,7 +3260,7 @@ class ReceiveCommits {
                       rw.markUninteresting(rw.parseCommit(cmd.getOldId()));
                     }
 
-                    Map<Change.Key, ChangeNotes> byKey = null;
+                    Map<Change.Key, ChangeData> changeDataByKey = null;
                     List<ReplaceRequest> replaceAndClose = new ArrayList<>();
 
                     int existingPatchSets = 0;
@@ -3297,8 +3297,8 @@ class ReceiveCommits {
                       }
 
                       for (String changeId : c.getFooterLines(FooterConstants.CHANGE_ID)) {
-                        if (byKey == null) {
-                          byKey =
+                        if (changeDataByKey == null) {
+                          changeDataByKey =
                               retryHelper
                                   .changeIndexQuery(
                                       "queryOpenChangesByKeyByBranch",
@@ -3306,14 +3306,15 @@ class ReceiveCommits {
                                   .call();
                         }
 
-                        ChangeNotes onto = byKey.get(Change.key(changeId.trim()));
+                        ChangeData onto = changeDataByKey.get(Change.key(changeId.trim()));
                         if (onto != null) {
                           newPatchSets++;
                           // Hold onto this until we're done with the walk, as the call to
                           // req.validate below calls isMergedInto which resets the walk.
+                          ChangeNotes ontoNotes = onto.notes();
                           ReplaceRequest req =
-                              new ReplaceRequest(onto.getChangeId(), c, cmd, false);
-                          req.notes = onto;
+                              new ReplaceRequest(ontoNotes.getChangeId(), c, cmd, false);
+                          req.notes = ontoNotes;
                           replaceAndClose.add(req);
                           continue COMMIT;
                         }
@@ -3384,14 +3385,17 @@ class ReceiveCommits {
     }
   }
 
-  private Map<Change.Key, ChangeNotes> openChangesByKeyByBranch(
+  private Map<Change.Key, ChangeData> openChangesByKeyByBranch(
       InternalChangeQuery internalChangeQuery, BranchNameKey branch) {
     try (TraceTimer traceTimer =
         newTimer("openChangesByKeyByBranch", Metadata.builder().branchName(branch.branch()))) {
-      Map<Change.Key, ChangeNotes> r = new HashMap<>();
+      Map<Change.Key, ChangeData> r = new HashMap<>();
       for (ChangeData cd : internalChangeQuery.byBranchOpen(branch)) {
         try {
-          r.put(cd.change().getKey(), cd.notes());
+          // ChangeData is not materialised into a ChangeNotes for avoiding
+          // to load a potentially large number of changes meta-data into memory
+          // which would cause unnecessary disk I/O, CPU and heap utilisation.
+          r.put(cd.change().getKey(), cd);
         } catch (NoSuchChangeException e) {
           // Ignore deleted change
         }