Use a hash map to avoid a presize vector.

3 files changed, 18 insertions, 12 deletions

diff --git a/searchlib/src/tests/docstore/logdatastore/logdatastore_test.cpp b/searchlib/src/tests/docstore/logdatastore/logdatastore_test.cpp
index ba7508f9b60..71712623a1d 100644
--- a/searchlib/src/tests/docstore/logdatastore/logdatastore_test.cpp
+++ b/searchlib/src/tests/docstore/logdatastore/logdatastore_test.cpp
@@ -1013,9 +1013,9 @@ TEST_F("require that lid space can be increased after being compacted and then s
 TEST_F("require that there is control of static memory usage", Fixture)
 {
     vespalib::MemoryUsage usage = f.store.getMemoryUsage();
-    EXPECT_EQUAL(584u, sizeof(LogDataStore));
-    EXPECT_EQUAL(2892160u, usage.allocatedBytes());
-    EXPECT_EQUAL(262536u, usage.usedBytes());
+    EXPECT_EQUAL(624u, sizeof(LogDataStore));
+    EXPECT_EQUAL(2630020u, usage.allocatedBytes());
+    EXPECT_EQUAL(392u, usage.usedBytes());
 }
 
 TEST_F("require that lid space can be shrunk only after read guards are deleted", Fixture)
diff --git a/searchlib/src/vespa/searchlib/docstore/logdatastore.cpp b/searchlib/src/vespa/searchlib/docstore/logdatastore.cpp
index 74c21423e2b..91ced8a66c5 100644
--- a/searchlib/src/vespa/searchlib/docstore/logdatastore.cpp
+++ b/searchlib/src/vespa/searchlib/docstore/logdatastore.cpp
@@ -83,7 +83,6 @@ LogDataStore::LogDataStore(vespalib::Executor &executor, const vespalib::string
 {
     // Reserve space for 1TB summary in order to avoid locking.
     _fileChunks.reserve(LidInfo::getFileIdLimit());
-    _holdFileChunks.resize(LidInfo::getFileIdLimit());
 
     preload();
     updateLidMap(getLastFileChunkDocIdLimit());
@@ -1129,9 +1128,13 @@ std::unique_ptr<LogDataStore::FileChunkHolder>
 LogDataStore::holdFileChunk(const MonitorGuard & guard, FileId fileId)
 {
     assert(guard.owns_lock());
-    assert(fileId.getId() < _holdFileChunks.size());
-    assert(_holdFileChunks[fileId.getId()] < 2000u);
-    ++_holdFileChunks[fileId.getId()];
+    auto found = _holdFileChunks.find(fileId.getId());
+    if (found == _holdFileChunks.end()) {
+        _holdFileChunks[fileId.getId()] = 1;
+    } else {
+        assert(found->second < 2000u);
+        found->second++;
+    }
     return std::make_unique<FileChunkHolder>(*this, fileId);
 }
 
@@ -1139,15 +1142,18 @@ void
 LogDataStore::unholdFileChunk(FileId fileId)
 {
     MonitorGuard guard(_updateLock);
-    assert(fileId.getId() < _holdFileChunks.size());
-    assert(_holdFileChunks[fileId.getId()] > 0u);
-    --_holdFileChunks[fileId.getId()];
+    auto found = _holdFileChunks.find(fileId.getId());
+    assert(found != _holdFileChunks.end());
+    assert(found->second > 0u);
+    if (--found->second == 0u) {
+        _holdFileChunks.erase(found);
+    }
     // No signalling, compactWorst() sleeps and retries
 }
 
 bool LogDataStore::canFileChunkBeDropped(const MonitorGuard & guard, FileId fileId) const {
     assert(guard.owns_lock());
-    return _holdFileChunks[fileId.getId()] == 0u;
+    return ! _holdFileChunks.contains(fileId.getId());
 }
 
 DataStoreStorageStats
diff --git a/searchlib/src/vespa/searchlib/docstore/logdatastore.h b/searchlib/src/vespa/searchlib/docstore/logdatastore.h
index 95605b87aaa..ef2cbf93215 100644
--- a/searchlib/src/vespa/searchlib/docstore/logdatastore.h
+++ b/searchlib/src/vespa/searchlib/docstore/logdatastore.h
@@ -254,7 +254,7 @@ private:
     mutable vespalib::GenerationHandler      _genHandler;
     LidInfoVector                            _lidInfo;
     FileChunkVector                          _fileChunks;
-    std::vector<uint32_t>                    _holdFileChunks;
+    vespalib::hash_map<uint32_t, uint32_t>   _holdFileChunks;
     FileId                                   _active;
     FileId                                   _prevActive;
     mutable std::mutex                       _updateLock;