Merge pull request #20666 from vespa-engine/balder/shrink-buffer-to-fit-if-overhead-is-larger-than-8xv7.523.17

If TLS buffer has more than 8x overhead, shrink it to fit prior to po…

4 files changed, 37 insertions, 0 deletions

diff --git a/searchlib/src/tests/transactionlog/chunks_test.cpp b/searchlib/src/tests/transactionlog/chunks_test.cpp
index 8d6620c9f8b..ca03a47634d 100644
--- a/searchlib/src/tests/transactionlog/chunks_test.cpp
+++ b/searchlib/src/tests/transactionlog/chunks_test.cpp
@@ -115,4 +115,25 @@ TEST("test multi element commitchunk") {
     }
     EXPECT_EQUAL(0u, counter);
 }
+
+TEST("shrinkToFit if difference is larger than 8x") {
+    Packet p(16000);
+    p.add(Packet::Entry(1, 3, ConstBufferRef(TEXT, strlen(TEXT))));
+    EXPECT_EQUAL(150u, p.sizeBytes());
+    EXPECT_EQUAL(16384u, p.getHandle().capacity());
+    p.shrinkToFit();
+    EXPECT_EQUAL(150u, p.sizeBytes());
+    EXPECT_EQUAL(150u, p.getHandle().capacity());
+}
+
+TEST("not shrinkToFit if difference is less than 8x") {
+    Packet p(1000);
+    p.add(Packet::Entry(1, 3, ConstBufferRef(TEXT, strlen(TEXT))));
+    EXPECT_EQUAL(150u, p.sizeBytes());
+    EXPECT_EQUAL(1024u, p.getHandle().capacity());
+    p.shrinkToFit();
+    EXPECT_EQUAL(150u, p.sizeBytes());
+    EXPECT_EQUAL(1024u, p.getHandle().capacity());
+}
+
 TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/searchlib/src/vespa/searchlib/transactionlog/common.cpp b/searchlib/src/vespa/searchlib/transactionlog/common.cpp
index 967f8748174..4130ad0bc06 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/common.cpp
+++ b/searchlib/src/vespa/searchlib/transactionlog/common.cpp
@@ -116,6 +116,14 @@ Packet::add(const Packet::Entry & e)
     _range.to(e.serial());
 }
 
+void
+Packet::shrinkToFit() {
+    if (_buf.size() * 8 < _buf.capacity()) {
+        nbostream::Buffer shrunkToFit(_buf.data(), _buf.data() + _buf.size());
+        _buf.swap(shrunkToFit);
+    }
+}
+
 Writer::CommitResult::CommitResult()
     : _callBacks()
 {}
@@ -151,4 +159,9 @@ CommitChunk::createCommitResult() const {
     return Writer::CommitResult(_callBacks);
 }
 
+void
+CommitChunk::shrinkPayloadToFit() {
+    _data.shrinkToFit();
+}
+
 }
diff --git a/searchlib/src/vespa/searchlib/transactionlog/common.h b/searchlib/src/vespa/searchlib/transactionlog/common.h
index 135681037ef..87150f2cfa9 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/common.h
+++ b/searchlib/src/vespa/searchlib/transactionlog/common.h
@@ -83,6 +83,7 @@ public:
     bool                   empty() const { return _count == 0; }
     size_t             sizeBytes() const { return _buf.size(); }
     void merge(const Packet & packet);
+    void shrinkToFit();
 private:
     size_t                            _count;
     SerialNumRange                    _range;
@@ -143,6 +144,7 @@ public:
     Writer::CommitResult createCommitResult() const;
     void setCommitDoneCallback(Writer::DoneCallback onDone) { _onCommitDone = std::move(onDone); }
     Writer::CommitPayload stealCallbacks() { return std::move(_callBacks); }
+    void shrinkPayloadToFit();
 private:
     Packet                 _data;
     Writer::CommitPayload  _callBacks;
diff --git a/searchlib/src/vespa/searchlib/transactionlog/domain.cpp b/searchlib/src/vespa/searchlib/transactionlog/domain.cpp
index bbde39a42f6..ff35847aa77 100644
--- a/searchlib/src/vespa/searchlib/transactionlog/domain.cpp
+++ b/searchlib/src/vespa/searchlib/transactionlog/domain.cpp
@@ -396,6 +396,7 @@ void
 Domain::commitChunk(std::unique_ptr<CommitChunk> chunk, const UniqueLock & chunkOrderGuard) {
     assert(chunkOrderGuard.mutex() == &_currentChunkMonitor && chunkOrderGuard.owns_lock());
     if (chunk->getPacket().empty()) return;
+    chunk->shrinkPayloadToFit();
     std::promise<SerializedChunk> promise;
     std::future<SerializedChunk> future = promise.get_future();
     _executor.execute(makeLambdaTask([promise=std::move(promise), chunk = std::move(chunk),