From cfab48793a27e13e78bae7f3b84c2f55e93d63e7 Mon Sep 17 00:00:00 2001
From: Marcin Czech <maczech@gmail.com>
Date: Mon, 12 Oct 2020 11:18:09 +0200
Subject: [PATCH] Use persistent cache provided by libModule for offline
 reindex

Gerrit offline reindexing ignores persistent cache implementation
provided as libModule and always generates caches using H2
implementation. This fix allows to use a different persistent cache
backend.

Using different cache implementation during the offline reindexing
and at runtime causes situation when Gerrit starts without any
precomputed caches which significantly impacts overall performance.
On the other hand offline reindexing cannot reuse existing caches
which impacts reindexing performance.

Bug: Issue 13464
Change-Id: I36305282e8ea583dfb37f629e41d219762c3b4a3
---
 java/com/google/gerrit/pgm/Reindex.java                 | 9 ++++++++-
 java/com/google/gerrit/pgm/util/BatchProgramModule.java | 3 +--
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/java/com/google/gerrit/pgm/Reindex.java b/java/com/google/gerrit/pgm/Reindex.java
index 966801f382..c8d69f1cc1 100644
--- a/java/com/google/gerrit/pgm/Reindex.java
+++ b/java/com/google/gerrit/pgm/Reindex.java
@@ -29,6 +29,10 @@ import com.google.gerrit.lifecycle.LifecycleManager;
 import com.google.gerrit.lucene.LuceneIndexModule;
 import com.google.gerrit.pgm.util.BatchProgramModule;
 import com.google.gerrit.pgm.util.SiteProgram;
+import com.google.gerrit.server.LibModuleLoader;
+import com.google.gerrit.server.LibModuleType;
+import com.google.gerrit.server.ModuleOverloader;
+import com.google.gerrit.server.cache.h2.H2CacheModule;
 import com.google.gerrit.server.change.ChangeResource;
 import com.google.gerrit.server.config.GerritServerConfig;
 import com.google.gerrit.server.index.IndexModule;
@@ -159,6 +163,7 @@ public class Reindex extends SiteProgram {
     }
     modules.add(indexModule);
     modules.add(new BatchProgramModule());
+    modules.add(new H2CacheModule());
     modules.add(
         new FactoryModule() {
           @Override
@@ -167,7 +172,9 @@ public class Reindex extends SiteProgram {
           }
         });
 
-    return dbInjector.createChildInjector(modules);
+    return dbInjector.createChildInjector(
+        ModuleOverloader.override(
+            modules, LibModuleLoader.loadModules(dbInjector, LibModuleType.SYS_MODULE)));
   }
 
   private void overrideConfig() {
diff --git a/java/com/google/gerrit/pgm/util/BatchProgramModule.java b/java/com/google/gerrit/pgm/util/BatchProgramModule.java
index 35ba3d0c86..e9c0136d83 100644
--- a/java/com/google/gerrit/pgm/util/BatchProgramModule.java
+++ b/java/com/google/gerrit/pgm/util/BatchProgramModule.java
@@ -38,7 +38,6 @@ import com.google.gerrit.server.account.Realm;
 import com.google.gerrit.server.account.ServiceUserClassifierImpl;
 import com.google.gerrit.server.account.externalids.ExternalIdModule;
 import com.google.gerrit.server.cache.CacheRemovalListener;
-import com.google.gerrit.server.cache.h2.H2CacheModule;
 import com.google.gerrit.server.cache.mem.DefaultMemoryCacheModule;
 import com.google.gerrit.server.change.ChangeAttributeFactory;
 import com.google.gerrit.server.change.ChangeJson;
@@ -153,7 +152,7 @@ public class BatchProgramModule extends FactoryModule {
     install(new BatchGitModule());
     install(new DefaultPermissionBackendModule());
     install(new DefaultMemoryCacheModule());
-    install(new H2CacheModule());
+
     install(new ExternalIdModule());
     install(new GroupModule());
     install(new NoteDbModule());