Repeat sync twice.

3 files changed, 11 insertions, 4 deletions

diff --git a/searchcore/src/vespa/searchcore/proton/server/documentdb.cpp b/searchcore/src/vespa/searchcore/proton/server/documentdb.cpp
index c6708500390..f509bcf31ef 100644
--- a/searchcore/src/vespa/searchcore/proton/server/documentdb.cpp
+++ b/searchcore/src/vespa/searchcore/proton/server/documentdb.cpp
@@ -895,7 +895,6 @@ DocumentDB::syncFeedView()
     IFeedView::SP newFeedView(_subDBs.getFeedView());
 
     _writeService.sync();
-    _writeService.sync(); // Needs a second sync as more task might be posted
 
     _feedView.set(newFeedView);
     _feedHandler->setActiveFeedView(newFeedView.get());
diff --git a/searchcore/src/vespa/searchcore/proton/server/executorthreadingservice.cpp b/searchcore/src/vespa/searchcore/proton/server/executorthreadingservice.cpp
index b29dd955ff3..0559ac2afba 100644
--- a/searchcore/src/vespa/searchcore/proton/server/executorthreadingservice.cpp
+++ b/searchcore/src/vespa/searchcore/proton/server/executorthreadingservice.cpp
@@ -53,8 +53,16 @@ ExecutorThreadingService::ExecutorThreadingService(vespalib::SyncableThreadExecu
 ExecutorThreadingService::~ExecutorThreadingService() = default;
 
 vespalib::Syncable &
-ExecutorThreadingService::sync()
-{
+ExecutorThreadingService::sync() {
+    // We have multiple patterns where task A posts to B which post back to A
+    for (size_t i = 0; i < 2; i++) {
+        syncOnce();
+    }
+    return *this;
+}
+
+void
+ExecutorThreadingService::syncOnce() {
     bool isMasterThread = _masterService.isCurrentThread();
     if (!isMasterThread) {
         _masterExecutor.sync();
@@ -67,7 +75,6 @@ ExecutorThreadingService::sync()
     if (!isMasterThread) {
         _masterExecutor.sync();
     }
-    return *this;
 }
 
 void
diff --git a/searchcore/src/vespa/searchcore/proton/server/executorthreadingservice.h b/searchcore/src/vespa/searchcore/proton/server/executorthreadingservice.h
index 280e50aea56..1561f5d6adc 100644
--- a/searchcore/src/vespa/searchcore/proton/server/executorthreadingservice.h
+++ b/searchcore/src/vespa/searchcore/proton/server/executorthreadingservice.h
@@ -28,6 +28,7 @@ private:
     std::unique_ptr<vespalib::ISequencedTaskExecutor>    _indexFieldWriter;
     std::unique_ptr<vespalib::ISequencedTaskExecutor>    _attributeFieldWriter;
 
+    void syncOnce();
 public:
     using OptimizeFor = vespalib::Executor::OptimizeFor;
     /**