Reduce visibility to avoid having to see everything.

23 files changed, 180 insertions, 141 deletions

diff --git a/fnet/src/vespa/fnet/task.cpp b/fnet/src/vespa/fnet/task.cpp
index 0888cba6582..f5263450e6a 100644
--- a/fnet/src/vespa/fnet/task.cpp
+++ b/fnet/src/vespa/fnet/task.cpp
@@ -14,9 +14,7 @@ FNET_Task::FNET_Task(FNET_Scheduler *scheduler)
 }
 
 
-FNET_Task::~FNET_Task()
-{
-}
+FNET_Task::~FNET_Task() = default;
 
 
 void
diff --git a/searchcore/src/vespa/searchcore/proton/metrics/trans_log_server_metrics.cpp b/searchcore/src/vespa/searchcore/proton/metrics/trans_log_server_metrics.cpp
index 85644c2111a..348adf5bf41 100644
--- a/searchcore/src/vespa/searchcore/proton/metrics/trans_log_server_metrics.cpp
+++ b/searchcore/src/vespa/searchcore/proton/metrics/trans_log_server_metrics.cpp
@@ -17,7 +17,7 @@ TransLogServerMetrics::DomainMetrics::DomainMetrics(metrics::MetricSet *parent,
 {
 }
 
-TransLogServerMetrics::DomainMetrics::~DomainMetrics() {}
+TransLogServerMetrics::DomainMetrics::~DomainMetrics() = default;
 
 void
 TransLogServerMetrics::DomainMetrics::update(const DomainInfo &stats)
@@ -66,7 +66,7 @@ TransLogServerMetrics::TransLogServerMetrics(metrics::MetricSet *parent)
 {
 }
 
-TransLogServerMetrics::~TransLogServerMetrics() { }
+TransLogServerMetrics::~TransLogServerMetrics() = default;
 
 void
 TransLogServerMetrics::update(const DomainStats &stats)
diff --git a/searchcore/src/vespa/searchcore/proton/metrics/trans_log_server_metrics.h b/searchcore/src/vespa/searchcore/proton/metrics/trans_log_server_metrics.h
index 830d643e93e..727b0c6304d 100644
--- a/searchcore/src/vespa/searchcore/proton/metrics/trans_log_server_metrics.h
+++ b/searchcore/src/vespa/searchcore/proton/metrics/trans_log_server_metrics.h
@@ -3,7 +3,7 @@
 #pragma once
 
 #include <vespa/metrics/metrics.h>
-#include <vespa/searchlib/transactionlog/domain.h>
+#include <vespa/searchlib/transactionlog/domainconfig.h>
 
 namespace proton {
 
diff --git a/searchcore/src/vespa/searchcore/proton/server/proton.cpp b/searchcore/src/vespa/searchcore/proton/server/proton.cpp
index b297dd860ea..c40f1263324 100644
--- a/searchcore/src/vespa/searchcore/proton/server/proton.cpp
+++ b/searchcore/src/vespa/searchcore/proton/server/proton.cpp
@@ -22,6 +22,7 @@
 #include <vespa/searchcore/proton/summaryengine/docsum_by_slime.h>
 #include <vespa/searchcore/proton/matchengine/matchengine.h>
 #include <vespa/searchlib/transactionlog/trans_log_server_explorer.h>
+#include <vespa/searchlib/transactionlog/translogserverapp.h>
 #include <vespa/searchlib/util/fileheadertk.h>
 #include <vespa/searchlib/common/packets.h>
 #include <vespa/document/base/exceptions.h>
diff --git a/searchcore/src/vespa/searchcore/proton/server/proton.h b/searchcore/src/vespa/searchcore/proton/server/proton.h
index 6b561ad5deb..55fd3594463 100644
--- a/searchcore/src/vespa/searchcore/proton/server/proton.h
+++ b/searchcore/src/vespa/searchcore/proton/server/proton.h
@@ -19,7 +19,6 @@
 #include <vespa/searchcore/proton/persistenceengine/persistenceengine.h>
 #include <vespa/searchlib/common/fileheadercontext.h>
 #include <vespa/searchlib/engine/monitorapi.h>
-#include <vespa/searchlib/transactionlog/translogserverapp.h>
 #include <vespa/vespalib/net/component_config_producer.h>
 #include <vespa/vespalib/net/generic_state_handler.h>
 #include <vespa/vespalib/net/json_get_handler.h>
@@ -31,7 +30,7 @@
 #include <shared_mutex>
 
 namespace vespalib { class StateServer; }
-
+namespace search::transactionlog { class TransLogServerApp; }
 namespace proton {
 
 class DiskMemUsageSampler;
@@ -52,12 +51,12 @@ class Proton : public IProtonConfigurerOwner,
                public vespalib::StateExplorer
 {
 private:
-    typedef search::transactionlog::TransLogServerApp     TLS;
-    typedef search::engine::MonitorRequest                MonitorRequest;
-    typedef search::engine::MonitorReply                  MonitorReply;
-    typedef search::engine::MonitorClient                 MonitorClient;
-    typedef std::map<DocTypeName, DocumentDB::SP>         DocumentDBMap;
-    typedef BootstrapConfig::ProtonConfigSP               ProtonConfigSP;
+    using TLS = search::transactionlog::TransLogServerApp;
+    using MonitorRequest = search::engine::MonitorRequest;
+    using MonitorReply = search::engine::MonitorReply;
+    using MonitorClient = search::engine::MonitorClient;
+    using DocumentDBMap = std::map<DocTypeName, DocumentDB::SP>;
+    using ProtonConfigSP = BootstrapConfig::ProtonConfigSP;
     using InitializeThreads = std::shared_ptr<vespalib::SyncableThreadExecutor>;
     using BucketSpace = document::BucketSpace;
 
@@ -91,7 +90,7 @@ private:
     MetricsUpdateHook               _metricsHook;
     std::unique_ptr<MetricsEngine>  _metricsEngine;
     ProtonFileHeaderContext         _fileHeaderContext;
-    TLS::UP                         _tls;
+    std::unique_ptr<TLS>            _tls;
     std::unique_ptr<DiskMemUsageSampler> _diskMemUsageSampler;
     PersistenceEngine::UP           _persistenceEngine;
     DocumentDBMap                   _documentDBMap;
diff --git a/searchlib/src/tests/transactionlog/translogclient_test.cpp b/searchlib/src/tests/transactionlog/translogclient_test.cpp
index b7eb56d1fd9..a20e0cc3aaa 100644
--- a/searchlib/src/tests/transactionlog/translogclient_test.cpp
+++ b/searchlib/src/tests/transactionlog/translogclient_test.cpp
@@ -256,7 +256,7 @@ fillDomainTest(TransLogClient::Session * s1, const vespalib::string & name)
     ASSERT_TRUE (s1->commit(vespalib::ConstBufferRef(b.getHandle().data(), b.getHandle().size())));
     EXPECT_EXCEPTION(s1->commit(vespalib::ConstBufferRef(a.getHandle().data(), a.getHandle().size())),
                      std::runtime_error,
-                     "commit failed with code -2. server says: Exception during commit on " + name + " : Incomming serial number(1) must be bigger than the last one (3).");
+                     "commit failed with code -2. server says: Exception during commit on " + name + " : Incoming serial number(1) must be bigger than the last one (3).");
     EXPECT_EQUAL(a.size(), 1u);
     EXPECT_EQUAL(a.range().from(), 1u);
     EXPECT_EQUAL(a.range().to(), 1u);
diff --git a/searchlib/src/vespa/searchlib/transactionlog/CMakeLists.txt b/searchlib/src/vespa/searchlib/transactionlog/CMakeLists.txt
index 4ead34552bd..5dca84a26c1 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/CMakeLists.txt
+++ b/searchlib/src/vespa/searchlib/transactionlog/CMakeLists.txt
@@ -4,6 +4,7 @@ vespa_add_library(searchlib_transactionlog OBJECT
     chunks.cpp
     common.cpp
     domain.cpp
+    domainconfig.cpp
     domainpart.cpp
     ichunk.cpp
     nosyncproxy.cpp
diff --git a/searchlib/src/vespa/searchlib/transactionlog/common.h b/searchlib/src/vespa/searchlib/transactionlog/common.h
index 0deceb2668a..5cb1d67d525 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/common.h
+++ b/searchlib/src/vespa/searchlib/transactionlog/common.h
@@ -90,8 +90,17 @@ int makeDirectory(const char * dir);
 class Writer {
 public:
     using DoneCallback = std::shared_ptr<IDestructorCallback>;
-    virtual ~Writer() { }
+    virtual ~Writer() = default;
     virtual void commit(const vespalib::string & domainName, const Packet & packet, DoneCallback done) = 0;
 };
 
+class Destination {
+public:
+    virtual ~Destination() = default;
+    virtual bool send(int32_t id, const vespalib::string & domain, const Packet & packet) = 0;
+    virtual bool sendDone(int32_t id, const vespalib::string & domain) = 0;
+    virtual bool connected() const = 0;
+    virtual bool ok() const = 0;
+};
+
 }
diff --git a/searchlib/src/vespa/searchlib/transactionlog/domain.cpp b/searchlib/src/vespa/searchlib/transactionlog/domain.cpp
index 6b47393336a..aaf70964068 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/domain.cpp
+++ b/searchlib/src/vespa/searchlib/transactionlog/domain.cpp
@@ -1,6 +1,8 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 
 #include "domain.h"
+#include "domainpart.h"
+#include "session.h"
 #include <vespa/vespalib/util/stringfmt.h>
 #include <vespa/vespalib/util/closuretask.h>
 #include <vespa/vespalib/io/fileutil.h>
@@ -15,10 +17,11 @@
 LOG_SETUP(".transactionlog.domain");
 
 using vespalib::string;
-using vespalib::make_string;
+using vespalib::make_string_short::fmt;
 using vespalib::LockGuard;
 using vespalib::makeTask;
 using vespalib::makeClosure;
+using vespalib::makeLambdaTask;
 using vespalib::Monitor;
 using vespalib::MonitorGuard;
 using search::common::FileHeaderContext;
@@ -29,14 +32,6 @@ namespace search::transactionlog {
 
 VESPA_THREAD_STACK_TAG(domain_commit_executor);
 
-DomainConfig::DomainConfig()
-    : _encoding(Encoding::Crc::xxh64, Encoding::Compression::none),
-      _compressionLevel(9),
-      _partSizeLimit(0x10000000), // 256M
-      _chunkSizeLimit(0x40000),   // 256k
-      _chunkAgeLimit(10ms)
-{ }
-
 Domain::Domain(const string &domainName, const string & baseDir, Executor & commitExecutor,
                Executor & sessionExecutor, const DomainConfig & cfg, const FileHeaderContext &fileHeaderContext)
     : _config(cfg),
@@ -60,10 +55,10 @@ Domain::Domain(const string &domainName, const string & baseDir, Executor & comm
 {
     int retval(0);
     if ((retval = makeDirectory(_baseDir.c_str())) != 0) {
-        throw runtime_error(make_string("Failed creating basedirectory %s r(%d), e(%d)", _baseDir.c_str(), retval, errno));
+        throw runtime_error(fmt("Failed creating basedirectory %s r(%d), e(%d)", _baseDir.c_str(), retval, errno));
     }
     if ((retval = makeDirectory(dir().c_str())) != 0) {
-        throw runtime_error(make_string("Failed creating domaindir %s r(%d), e(%d)", dir().c_str(), retval, errno));
+        throw runtime_error(fmt("Failed creating domaindir %s r(%d), e(%d)", dir().c_str(), retval, errno));
     }
     SerialNumList partIdVector = scanDir();
     const int64_t lastPart = partIdVector.empty() ? 0 : partIdVector.back();
@@ -356,7 +351,7 @@ Domain::erase(SerialNum to)
 
 int
 Domain::visit(const Domain::SP & domain, SerialNum from, SerialNum to,
-              std::unique_ptr<Session::Destination> dest)
+              std::unique_ptr<Destination> dest)
 {
     assert(this == domain.get());
     cleanSessions();
@@ -442,7 +437,7 @@ Domain::scanDir()
             continue;
         const char *p = ename + wantPrefixLen + 1;
         uint64_t num = strtoull(p, NULL, 10);
-        string checkName = make_string("%s-%016" PRIu64, _name.c_str(), num);
+        string checkName = fmt("%s-%016" PRIu64, _name.c_str(), num);
         if (strcmp(checkName.c_str(), ename) != 0)
             continue;
         res.push_back(static_cast<SerialNum>(num));
diff --git a/searchlib/src/vespa/searchlib/transactionlog/domain.h b/searchlib/src/vespa/searchlib/transactionlog/domain.h
index a6c6dad5fe8..9c8b578a2c9 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/domain.h
+++ b/searchlib/src/vespa/searchlib/transactionlog/domain.h
@@ -1,70 +1,23 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 #pragma once
 
-#include "domainpart.h"
-#include "session.h"
+#include "domainconfig.h"
+#include <vespa/vespalib/util/sync.h>
 #include <vespa/vespalib/util/threadexecutor.h>
-#include <vespa/vespalib/util/time.h>
-#include <vespa/fastos/thread.h>
-#include <chrono>
+#include <atomic>
 
+namespace search::common { class FileHeaderContext; }
 namespace search::transactionlog {
 
-class DomainConfig {
-public:
-    using duration = vespalib::duration;
-    DomainConfig();
-    DomainConfig & setEncoding(Encoding v)          { _encoding = v; return *this; }
-    DomainConfig & setPartSizeLimit(size_t v)       { _partSizeLimit = v; return *this; }
-    DomainConfig & setChunkSizeLimit(size_t v)      { _chunkSizeLimit = v; return *this; }
-    DomainConfig & setChunkAgeLimit(vespalib::duration v) { _chunkAgeLimit = v; return *this; }
-    DomainConfig & setCompressionLevel(uint8_t v)   { _compressionLevel = v; return *this; }
-    Encoding          getEncoding() const { return _encoding; }
-    size_t       getPartSizeLimit() const { return _partSizeLimit; }
-    size_t      getChunkSizeLimit() const { return _chunkSizeLimit; }
-    duration     getChunkAgeLimit() const { return _chunkAgeLimit; }
-    uint8_t   getCompressionlevel() const { return _compressionLevel; }
-private:
-    Encoding     _encoding;
-    uint8_t      _compressionLevel;
-    size_t       _partSizeLimit;
-    size_t       _chunkSizeLimit;
-    duration     _chunkAgeLimit;
-};
-
-struct PartInfo {
-    SerialNumRange range;
-    size_t numEntries;
-    size_t byteSize;
-    vespalib::string file;
-    PartInfo(SerialNumRange range_in, size_t numEntries_in, size_t byteSize_in, vespalib::stringref file_in)
-        : range(range_in),
-          numEntries(numEntries_in),
-          byteSize(byteSize_in),
-          file(file_in)
-    {}
-};
-
-struct DomainInfo {
-    using DurationSeconds = std::chrono::duration<double>;
-    SerialNumRange range;
-    size_t numEntries;
-    size_t byteSize;
-    DurationSeconds maxSessionRunTime;
-    std::vector<PartInfo> parts;
-    DomainInfo(SerialNumRange range_in, size_t numEntries_in, size_t byteSize_in, DurationSeconds maxSessionRunTime_in)
-        : range(range_in), numEntries(numEntries_in), byteSize(byteSize_in), maxSessionRunTime(maxSessionRunTime_in), parts() {}
-    DomainInfo()
-        : range(), numEntries(0), byteSize(0), maxSessionRunTime(), parts() {}
-};
-
-typedef std::map<vespalib::string, DomainInfo> DomainStats;
+class DomainPart;
+class Session;
 
 class Domain
 {
 public:
     using SP = std::shared_ptr<Domain>;
     using Executor = vespalib::SyncableThreadExecutor;
+    using DomainPartSP = std::shared_ptr<DomainPart>;
     Domain(const vespalib::string &name, const vespalib::string &baseDir, Executor & commitExecutor,
            Executor & sessionExecutor, const DomainConfig & cfg, const common::FileHeaderContext &fileHeaderContext);
 
@@ -75,12 +28,13 @@ public:
     bool erase(SerialNum to);
 
     void commit(const Packet & packet, Writer::DoneCallback onDone);
-    int visit(const Domain::SP & self, SerialNum from, SerialNum to, std::unique_ptr<Session::Destination> dest);
+    int visit(const Domain::SP & self, SerialNum from, SerialNum to, std::unique_ptr<Destination> dest);
 
     SerialNum begin() const;
     SerialNum end() const;
     SerialNum getSynced() const;
     void triggerSyncNow();
+    bool commitIfStale();
     bool getMarkedDeleted() const { return _markedDeleted; }
     void markDeleted() { _markedDeleted = true; }
 
@@ -91,7 +45,7 @@ public:
     int closeSession(int sessionId);
 
     SerialNum findOldestActiveVisit() const;
-    DomainPart::SP findPart(SerialNum s);
+    DomainPartSP findPart(SerialNum s);
 
     static vespalib::string
     getDir(const vespalib::string & base, const vespalib::string & domain) {
@@ -115,8 +69,8 @@ private:
 
     SerialNumList scanDir();
 
-    using SessionList = std::map<int, Session::SP>;
-    using DomainPartList = std::map<int64_t, DomainPart::SP>;
+    using SessionList = std::map<int, std::shared_ptr<Session>>;
+    using DomainPartList = std::map<int64_t, DomainPartSP>;
     using DurationSeconds = std::chrono::duration<double>;
 
     DomainConfig           _config;
diff --git a/searchlib/src/vespa/searchlib/transactionlog/domainconfig.cpp b/searchlib/src/vespa/searchlib/transactionlog/domainconfig.cpp
new file mode 100644
index 00000000000..beac8cf714b
--- /dev/null
+++ b/searchlib/src/vespa/searchlib/transactionlog/domainconfig.cpp
@@ -0,0 +1,16 @@
+// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "domainconfig.h"
+
+namespace search::transactionlog {
+
+DomainConfig::DomainConfig()
+    : _encoding(Encoding::Crc::xxh64, Encoding::Compression::none),
+      _compressionLevel(9),
+      _fSyncOnCommit(false),
+      _partSizeLimit(0x10000000), // 256M
+      _chunkSizeLimit(0x40000),   // 256k
+      _chunkAgeLimit(10ms)
+{ }
+
+}
diff --git a/searchlib/src/vespa/searchlib/transactionlog/domainconfig.h b/searchlib/src/vespa/searchlib/transactionlog/domainconfig.h
new file mode 100644
index 00000000000..ada1e20e095
--- /dev/null
+++ b/searchlib/src/vespa/searchlib/transactionlog/domainconfig.h
@@ -0,0 +1,63 @@
+// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include "ichunk.h"
+#include <vespa/vespalib/util/time.h>
+#include <map>
+
+namespace search::transactionlog {
+
+class DomainConfig {
+public:
+    using duration = vespalib::duration;
+    DomainConfig();
+    DomainConfig & setEncoding(Encoding v)          { _encoding = v; return *this; }
+    DomainConfig & setPartSizeLimit(size_t v)       { _partSizeLimit = v; return *this; }
+    DomainConfig & setChunkSizeLimit(size_t v)      { _chunkSizeLimit = v; return *this; }
+    DomainConfig & setChunkAgeLimit(vespalib::duration v) { _chunkAgeLimit = v; return *this; }
+    DomainConfig & setCompressionLevel(uint8_t v)   { _compressionLevel = v; return *this; }
+    DomainConfig & setFSyncOnCommit(bool v)         { _fSyncOnCommit = v; return *this; }
+    Encoding          getEncoding() const { return _encoding; }
+    size_t       getPartSizeLimit() const { return _partSizeLimit; }
+    size_t      getChunkSizeLimit() const { return _chunkSizeLimit; }
+    duration     getChunkAgeLimit() const { return _chunkAgeLimit; }
+    uint8_t   getCompressionlevel() const { return _compressionLevel; }
+    bool         getFSyncOnCommit() const { return _fSyncOnCommit; }
+private:
+    Encoding     _encoding;
+    uint8_t      _compressionLevel;
+    bool         _fSyncOnCommit;
+    size_t       _partSizeLimit;
+    size_t       _chunkSizeLimit;
+    duration     _chunkAgeLimit;
+};
+
+struct PartInfo {
+    SerialNumRange range;
+    size_t numEntries;
+    size_t byteSize;
+    vespalib::string file;
+    PartInfo(SerialNumRange range_in, size_t numEntries_in, size_t byteSize_in, vespalib::stringref file_in)
+            : range(range_in),
+              numEntries(numEntries_in),
+              byteSize(byteSize_in),
+              file(file_in)
+    {}
+};
+
+struct DomainInfo {
+    using DurationSeconds = std::chrono::duration<double>;
+    SerialNumRange range;
+    size_t numEntries;
+    size_t byteSize;
+    DurationSeconds maxSessionRunTime;
+    std::vector<PartInfo> parts;
+    DomainInfo(SerialNumRange range_in, size_t numEntries_in, size_t byteSize_in, DurationSeconds maxSessionRunTime_in)
+            : range(range_in), numEntries(numEntries_in), byteSize(byteSize_in), maxSessionRunTime(maxSessionRunTime_in), parts() {}
+    DomainInfo()
+            : range(), numEntries(0), byteSize(0), maxSessionRunTime(), parts() {}
+};
+
+using DomainStats = std::map<vespalib::string, DomainInfo>;
+
+}
diff --git a/searchlib/src/vespa/searchlib/transactionlog/domainpart.cpp b/searchlib/src/vespa/searchlib/transactionlog/domainpart.cpp
index 96e75c35a81..8855183226d 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/domainpart.cpp
+++ b/searchlib/src/vespa/searchlib/transactionlog/domainpart.cpp
@@ -409,7 +409,7 @@ DomainPart::commit(SerialNum firstSerial, const Packet &packet)
             _sz++;
             _range.to(entry.serial());
         } else {
-            throw runtime_error(fmt("Incomming serial number(%" PRIu64 ") must be bigger than the last one (%" PRIu64 ").",
+            throw runtime_error(fmt("Incoming serial number(%" PRIu64 ") must be bigger than the last one (%" PRIu64 ").",
                                     entry.serial(), _range.to()));
         }
     }
@@ -429,7 +429,8 @@ DomainPart::commit(SerialNum firstSerial, const Packet &packet)
     }
 }
 
-void DomainPart::sync()
+void
+DomainPart::sync()
 {
     SerialNum syncSerial(0);
     {
@@ -449,7 +450,7 @@ DomainPart::visit(SerialNumRange &r, Packet &packet)
 {
     bool retval(false);
     LockGuard guard(_lock);
-    LOG(debug, "Visit r(%" PRIu64 ", %" PRIu64 "] Checking %" PRIu64 " packets",
+    LOG(spam, "Visit r(%" PRIu64 ", %" PRIu64 "] Checking %" PRIu64 " packets",
                r.from(), r.to(), uint64_t(_packets.size()));
     if ( ! isClosed() ) {
         PacketList::const_iterator start(_packets.lower_bound(r.from() + 1));
@@ -474,7 +475,7 @@ DomainPart::visit(SerialNumRange &r, Packet &packet)
                 ((next != end) || ((next != _packets.end()) && ((r.to() + 1) == next->first))))
             {
                 packet = start->second;
-                LOG(debug, "Visit whole packet[%" PRIu64 ", %" PRIu64 "]", packet.range().from(), packet.range().to());
+                LOG(spam, "Visit whole packet[%" PRIu64 ", %" PRIu64 "]", packet.range().from(), packet.range().to());
                 if (next != _packets.end()) {
                     r.from(next->first - 1);
                     retval = true;
@@ -484,7 +485,7 @@ DomainPart::visit(SerialNumRange &r, Packet &packet)
             } else {
                 const nbostream & tmp = start->second.getHandle();
                 nbostream_longlivedbuf h(tmp.data(), tmp.size());
-                LOG(debug, "Visit partial[%" PRIu64 ", %" PRIu64 "] (%zd, %zd, %zd)",
+                LOG(spam, "Visit partial[%" PRIu64 ", %" PRIu64 "] (%zd, %zd, %zd)",
                            start->second.range().from(), start->second.range().to(), h.rp(), h.size(), h.capacity());
                 Packet newPacket(h.size());
                 for (; (h.size() > 0) && (r.from() < r.to()); ) {
@@ -546,6 +547,8 @@ DomainPart::write(FastOS_FileInterface &file, const IChunk & chunk)
     if ( ! file.CheckedWrite(os.data(), os.size()) ) {
         throw runtime_error(handleWriteError("Failed writing the entry.", file, byteSize(), chunk.range(), os.size()));
     }
+    LOG(debug, "Wrote chunk with %zu entries and %zu bytes, range[%" PRIu64 ", %" PRIu64 "] encoding(wanted=%x, real=%x)",
+        chunk.getEntries().size(), os.size(), chunk.range().from(), chunk.range().to(), _encoding.getRaw(), realEncoding.getRaw());
     _writtenSerial = chunk.range().to();
     _byteSize.fetch_add(os.size(), std::memory_order_release);
 }
diff --git a/searchlib/src/vespa/searchlib/transactionlog/domainpart.h b/searchlib/src/vespa/searchlib/transactionlog/domainpart.h
index 5256b731125..31d6938b654 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/domainpart.h
+++ b/searchlib/src/vespa/searchlib/transactionlog/domainpart.h
@@ -15,12 +15,10 @@ namespace search::common { class FileHeaderContext; }
 namespace search::transactionlog {
 
 class DomainPart {
-private:
-    DomainPart(const DomainPart &);
-    DomainPart& operator=(const DomainPart &);
-
 public:
-    typedef std::shared_ptr<DomainPart> SP;
+    using SP = std::shared_ptr<DomainPart>;
+    DomainPart(const DomainPart &) = delete;
+    DomainPart& operator=(const DomainPart &) = delete;
     DomainPart(const vespalib::string &name, const vespalib::string &baseDir, SerialNum s, Encoding defaultEncoding,
                uint8_t compressionLevel, const common::FileHeaderContext &FileHeaderContext, bool allowTruncate);
 
diff --git a/searchlib/src/vespa/searchlib/transactionlog/ichunk.h b/searchlib/src/vespa/searchlib/transactionlog/ichunk.h
index aa2a2085aab..722aae828db 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/ichunk.h
+++ b/searchlib/src/vespa/searchlib/transactionlog/ichunk.h
@@ -3,9 +3,6 @@
 #pragma once
 
 #include "common.h"
-#include <memory>
-
-namespace vespalib { class nbostream; }
 
 namespace search::transactionlog {
 
diff --git a/searchlib/src/vespa/searchlib/transactionlog/session.cpp b/searchlib/src/vespa/searchlib/transactionlog/session.cpp
index dda840808ce..c91b719be37 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/session.cpp
+++ b/searchlib/src/vespa/searchlib/transactionlog/session.cpp
@@ -1,6 +1,7 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 #include "session.h"
 #include "domain.h"
+#include "domainpart.h"
 #include <vespa/fastlib/io/bufferedfile.h>
 #include <vespa/log/log.h>
 
diff --git a/searchlib/src/vespa/searchlib/transactionlog/session.h b/searchlib/src/vespa/searchlib/transactionlog/session.h
index 9b8d23371e8..ddbe218ed4e 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/session.h
+++ b/searchlib/src/vespa/searchlib/transactionlog/session.h
@@ -23,14 +23,6 @@ private:
     using time_point = std::chrono::time_point<std::chrono::steady_clock>;
 
 public:
-    class Destination {
-    public:
-        virtual ~Destination() = default;
-        virtual bool send(int32_t id, const vespalib::string & domain, const Packet & packet) = 0;
-        virtual bool sendDone(int32_t id, const vespalib::string & domain) = 0;
-        virtual bool connected() const = 0;
-        virtual bool ok() const = 0;
-    };
     typedef std::shared_ptr<Session> SP;
     Session(const Session &) = delete;
     Session & operator = (const Session &) = delete;
diff --git a/searchlib/src/vespa/searchlib/transactionlog/trans_log_server_explorer.cpp b/searchlib/src/vespa/searchlib/transactionlog/trans_log_server_explorer.cpp
index 1d1edbed658..bdf12ab64e8 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/trans_log_server_explorer.cpp
+++ b/searchlib/src/vespa/searchlib/transactionlog/trans_log_server_explorer.cpp
@@ -1,6 +1,8 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 
 #include "trans_log_server_explorer.h"
+#include "translogserver.h"
+#include "domain.h"
 #include <vespa/vespalib/data/slime/slime.h>
 #include <vespa/vespalib/util/time.h>
 #include <vespa/fastos/file.h>
@@ -44,6 +46,7 @@ struct DomainExplorer : vespalib::StateExplorer {
 
 } // namespace search::transactionlog::<unnamed>
 
+TransLogServerExplorer::~TransLogServerExplorer() = default;
 void
 TransLogServerExplorer::get_state(const Inserter &inserter, bool full) const
 {
diff --git a/searchlib/src/vespa/searchlib/transactionlog/trans_log_server_explorer.h b/searchlib/src/vespa/searchlib/transactionlog/trans_log_server_explorer.h
index 65d3a687bc9..66fb1698104 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/trans_log_server_explorer.h
+++ b/searchlib/src/vespa/searchlib/transactionlog/trans_log_server_explorer.h
@@ -2,24 +2,27 @@
 
 #pragma once
 
-#include "translogserver.h"
 #include <vespa/vespalib/net/state_explorer.h>
 
 namespace search::transactionlog {
 
+class TransLogServer;
+
 /**
  * Class used to explore the state of a transaction log server.
  */
 class TransLogServerExplorer : public vespalib::StateExplorer
 {
 private:
-    TransLogServer::SP _server;
+    using TransLogServerSP = std::shared_ptr<TransLogServer>;
+    TransLogServerSP _server;
 
 public:
-    TransLogServerExplorer(TransLogServer::SP server) : _server(std::move(server)) {}
-    virtual void get_state(const vespalib::slime::Inserter &inserter, bool full) const override;
-    virtual std::vector<vespalib::string> get_children_names() const override;
-    virtual std::unique_ptr<StateExplorer> get_child(vespalib::stringref name) const override;
+    TransLogServerExplorer(TransLogServerSP server) : _server(std::move(server)) {}
+    ~TransLogServerExplorer() override;
+    void get_state(const vespalib::slime::Inserter &inserter, bool full) const override;
+    std::vector<vespalib::string> get_children_names() const override;
+    std::unique_ptr<StateExplorer> get_child(vespalib::stringref name) const override;
 };
 
 }
diff --git a/searchlib/src/vespa/searchlib/transactionlog/translogserver.cpp b/searchlib/src/vespa/searchlib/transactionlog/translogserver.cpp
index edfbf846688..93b65002492 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/translogserver.cpp
+++ b/searchlib/src/vespa/searchlib/transactionlog/translogserver.cpp
@@ -1,9 +1,9 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 #include "translogserver.h"
+#include "domain.h"
 #include <vespa/searchlib/common/gatecallback.h>
 #include <vespa/vespalib/util/stringfmt.h>
 #include <vespa/vespalib/io/fileutil.h>
-#include <vespa/vespalib/util/time.h>
 #include <vespa/vespalib/util/exceptions.h>
 #include <vespa/fnet/frt/supervisor.h>
 #include <vespa/fnet/frt/rpcrequest.h>
@@ -42,7 +42,6 @@ public:
     void PerformTask() override;
 };
 
-
 SyncHandler::SyncHandler(FRT_Supervisor *supervisor, FRT_RPCRequest *req, const Domain::SP &domain,
                          const TransLogServer::Session::SP &session, SerialNum syncTo)
     : FNET_Task(supervisor->GetScheduler()),
@@ -53,10 +52,8 @@ SyncHandler::SyncHandler(FRT_Supervisor *supervisor, FRT_RPCRequest *req, const
 {
 }
 
-
 SyncHandler::~SyncHandler() = default;
 
-
 void
 SyncHandler::PerformTask()
 {
@@ -207,10 +204,16 @@ TransLogServer::run()
     LOG(info, "TLS Stopped");
 }
 
+vespalib::duration
+TransLogServer::getChunkAgeLimit() const
+{
+    Guard domainGuard(_domainMutex);
+    return _domainConfig.getChunkAgeLimit();
+}
 
 TransLogServer &
 TransLogServer::setDomainConfig(const DomainConfig & cfg) {
-    Guard domainGuard(_lock);
+    Guard domainGuard(_domainMutex);
     _domainConfig = cfg;
     for(auto &domain: _domains) {
         domain.second->setConfig(cfg);
@@ -222,7 +225,7 @@ DomainStats
 TransLogServer::getDomainStats() const
 {
     DomainStats retval;
-    Guard domainGuard(_lock);
+    Guard domainGuard(_domainMutex);
     for (const auto &elem : _domains) {
         retval[elem.first] = elem.second->getDomainInfo();
     }
@@ -233,7 +236,7 @@ std::vector<vespalib::string>
 TransLogServer::getDomainNames()
 {
     std::vector<vespalib::string> names;
-    Guard guard(_lock);
+    Guard guard(_domainMutex);
     for(const auto &domain: _domains) {
         names.push_back(domain.first);
     }
@@ -243,7 +246,7 @@ TransLogServer::getDomainNames()
 Domain::SP
 TransLogServer::findDomain(stringref domainName)
 {
-    Guard domainGuard(_lock);
+    Guard domainGuard(_domainMutex);
     Domain::SP domain;
     DomainList::iterator found(_domains.find(domainName));
     if (found != _domains.end()) {
@@ -363,7 +366,7 @@ writeDomainDir(std::lock_guard<std::mutex> &guard,
     vespalib::File::sync(dir);
 }
 
-class RPCDestination : public Session::Destination {
+class RPCDestination : public Destination {
 public:
     RPCDestination(FRT_Supervisor & supervisor, FNET_Connection * connection)
         : _supervisor(supervisor), _connection(connection), _ok(true)
@@ -448,7 +451,7 @@ TransLogServer::createDomain(FRT_RPCRequest *req)
         try {
             domain = std::make_shared<Domain>(domainName, dir(), _commitExecutor,
                                               _sessionExecutor, _domainConfig, _fileHeaderContext);
-            Guard domainGuard(_lock);
+            Guard domainGuard(_domainMutex);
             _domains[domain->name()] = domain;
             writeDomainDir(domainGuard, dir(), domainList(), _domains);
         } catch (const std::exception & e) {
@@ -477,12 +480,12 @@ TransLogServer::deleteDomain(FRT_RPCRequest *req)
         try {
             if (domain) {
                 domain->markDeleted();
-                Guard domainGuard(_lock);
+                Guard domainGuard(_domainMutex);
                 _domains.erase(domainName);
             }
             vespalib::rmdir(Domain::getDir(dir(), domainName), true);
             vespalib::File::sync(dir());
-            Guard domainGuard(_lock);
+            Guard domainGuard(_domainMutex);
             writeDomainDir(domainGuard, dir(), domainList(), _domains);
         } catch (const std::exception & e) {
             msg = make_string("Failed deleting %s domain. Exception = %s", domainName, e.what());
@@ -523,7 +526,7 @@ TransLogServer::listDomains(FRT_RPCRequest *req)
     LOG(debug, "listDomains()");
 
     vespalib::string domains;
-    Guard domainGuard(_lock);
+    Guard domainGuard(_domainMutex);
     for(DomainList::const_iterator it(_domains.begin()), mt(_domains.end()); it != mt; it++) {
         domains += it->second->name();
         domains += "\n";
diff --git a/searchlib/src/vespa/searchlib/transactionlog/translogserver.h b/searchlib/src/vespa/searchlib/transactionlog/translogserver.h
index 3f945977386..9351f3244dd 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/translogserver.h
+++ b/searchlib/src/vespa/searchlib/transactionlog/translogserver.h
@@ -1,30 +1,29 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 #pragma once
 
-#include "domain.h"
+#include "domainconfig.h"
 #include <vespa/vespalib/util/document_runnable.h>
 #include <vespa/vespalib/util/threadstackexecutor.h>
 #include <vespa/document/util/queue.h>
 #include <vespa/fnet/frt/invokable.h>
 #include <mutex>
 
-
 class FRT_Supervisor;
 class FNET_Transport;
 
+namespace std {class thread; }
 namespace search::common { class FileHeaderContext; }
-
 namespace search::transactionlog {
 
 class TransLogServerExplorer;
+class Domain;
 
 class TransLogServer : public document::Runnable, private FRT_Invokable, public Writer
 {
 public:
     friend class TransLogServerExplorer;
-    typedef std::unique_ptr<TransLogServer> UP;
-    typedef std::shared_ptr<TransLogServer> SP;
-
+    using SP = std::shared_ptr<TransLogServer>;
+    using DomainSP = std::shared_ptr<Domain>;
     TransLogServer(const vespalib::string &name, int listenPort, const vespalib::string &baseDir,
                    const common::FileHeaderContext &fileHeaderContext, const DomainConfig & cfg, size_t maxThreads);
     TransLogServer(const vespalib::string &name, int listenPort, const vespalib::string &baseDir,
@@ -33,8 +32,10 @@ public:
                    const common::FileHeaderContext &fileHeaderContext);
     ~TransLogServer() override;
     DomainStats getDomainStats() const;
+    bool commitIfStale();
     void commit(const vespalib::string & domainName, const Packet & packet, DoneCallback done) override;
     TransLogServer & setDomainConfig(const DomainConfig & cfg);
+    vespalib::duration getChunkAgeLimit() const;
 
     class Session
     {
@@ -71,13 +72,13 @@ private:
     void downSession(FRT_RPCRequest *req);
 
     std::vector<vespalib::string> getDomainNames();
-    Domain::SP findDomain(vespalib::stringref name);
+    DomainSP findDomain(vespalib::stringref name);
     vespalib::string dir()        const { return _baseDir + "/" + _name; }
     vespalib::string domainList() const { return dir() + "/" + _name + ".domains"; }
 
     static const Session::SP & getSession(FRT_RPCRequest *req);
 
-    using DomainList = std::map<vespalib::string, Domain::SP >;
+    using DomainList = std::map<vespalib::string, DomainSP >;
 
     vespalib::string                    _name;
     vespalib::string                    _baseDir;
@@ -87,12 +88,15 @@ private:
     std::unique_ptr<FastOS_ThreadPool>  _threadPool;
     std::unique_ptr<FNET_Transport>     _transport;
     std::unique_ptr<FRT_Supervisor>     _supervisor;
+    std::unique_ptr<std::thread>        _staleCommitThread;
     DomainList                          _domains;
-    mutable std::mutex                  _lock;          // Protects _domains
+    mutable std::mutex                  _domainMutex;          // Protects _domains
+    std::condition_variable             _domainCondition;
     std::mutex                          _fileLock;      // Protects the creating and deleting domains including file system operations.
     document::Queue<FRT_RPCRequest *>   _reqQ;
     const common::FileHeaderContext    &_fileHeaderContext;
     using Guard = std::lock_guard<std::mutex>;
+    using MonitorGuard = std::unique_lock<std::mutex>;
 };
 
 }
diff --git a/searchlib/src/vespa/searchlib/transactionlog/translogserverapp.cpp b/searchlib/src/vespa/searchlib/transactionlog/translogserverapp.cpp
index d83623661ff..12c38ab5739 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/translogserverapp.cpp
+++ b/searchlib/src/vespa/searchlib/transactionlog/translogserverapp.cpp
@@ -66,7 +66,8 @@ getDomainConfig(const searchlib::TranslogserverConfig & cfg) {
         .setCompressionLevel(cfg.compression.level)
         .setPartSizeLimit(cfg.filesizemax)
         .setChunkSizeLimit(cfg.chunk.sizelimit)
-        .setChunkAgeLimit(vespalib::from_s(cfg.chunk.agelimit));
+        .setChunkAgeLimit(vespalib::from_s(cfg.chunk.agelimit))
+        .setFSyncOnCommit(cfg.usefsync);
     return dcfg;
 }
 
diff --git a/searchlib/src/vespa/searchlib/transactionlog/translogserverapp.h b/searchlib/src/vespa/searchlib/transactionlog/translogserverapp.h
index d46805c105c..fb93559c29f 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/translogserverapp.h
+++ b/searchlib/src/vespa/searchlib/transactionlog/translogserverapp.h
@@ -23,11 +23,9 @@ private:
     void configure(std::unique_ptr<searchlib::TranslogserverConfig> cfg) override ;
 
 public:
-    typedef std::unique_ptr<TransLogServerApp> UP;
-
     TransLogServerApp(const config::ConfigUri & tlsConfigUri,
                       const common::FileHeaderContext &fileHeaderContext);
-    ~TransLogServerApp();
+    ~TransLogServerApp() override;
 
     TransLogServer::SP getTransLogServer() const;