/// <summary> /// Needs to take the flushing lock. Called only from <see cref="FlushAsync(OperationContext)"/>. Refactored /// out for clarity. /// </summary> private void PerformFlush(OperationContext context) { _database.Counters[ContentLocationDatabaseCounters.TotalNumberOfCacheFlushes].Increment(); using (_database.Counters[ContentLocationDatabaseCounters.CacheFlush].Start()) { using (_exchangeLock.AcquireWriteLock()) { _flushingCache = _cache; _cache = new ConcurrentBigMap <ShortHash, ContentLocationEntry>(); } if (_configuration.FlushSingleTransaction) { _database.PersistBatch(context, _flushingCache); } else { var actionBlock = new ActionBlockSlim <KeyValuePair <ShortHash, ContentLocationEntry> >(_configuration.FlushDegreeOfParallelism, kv => { // Do not lock on GetLock here, as it will cause a deadlock with // SetMachineExistenceAndUpdateDatabase. It is correct not do take any locks as well, because // no Store can happen while flush is running. _database.Persist(context, kv.Key, kv.Value); }); foreach (var kv in _flushingCache) { actionBlock.Post(kv); } actionBlock.Complete(); actionBlock.CompletionAsync().Wait(); } _database.Counters[ContentLocationDatabaseCounters.NumberOfPersistedEntries].Add(_flushingCache.Count); if (_configuration.FlushPreservePercentInMemory > 0) { int targetFlushingSize = (int)(_flushingCache.Count * _configuration.FlushPreservePercentInMemory); int removeAmount = _flushingCache.Count - targetFlushingSize; foreach (var key in _flushingCache.Keys.Take(removeAmount)) { _flushingCache.RemoveKey(key); } } else { using (_exchangeLock.AcquireWriteLock()) { _flushingCache = new ConcurrentBigMap <ShortHash, ContentLocationEntry>(); } } _database.Counters[ContentLocationDatabaseCounters.TotalNumberOfCompletedCacheFlushes].Increment(); } }
/// <summary> /// Needs to take the flushing lock. Called only from <see cref="FlushAsync(OperationContext)"/>. Refactored /// out for clarity. /// </summary> private CounterCollection <FlushableCacheCounters> PerformFlush(OperationContext context) { _database.Counters[ContentLocationDatabaseCounters.TotalNumberOfCacheFlushes].Increment(); var counters = new CounterCollection <FlushableCacheCounters>(); using (_database.Counters[ContentLocationDatabaseCounters.CacheFlush].Start()) { using (_exchangeLock.AcquireWriteLock()) { _flushingCache = _cache; _cache = new ConcurrentBigMap <ShortHash, ContentLocationEntry>(); } using (counters[FlushableCacheCounters.FlushingTime].Start()) { var threads = _configuration.FlushDegreeOfParallelism; if (threads <= 0) { threads = Environment.ProcessorCount; } if (_configuration.FlushSingleTransaction) { if (_configuration.FlushDegreeOfParallelism == 1 || _flushingCache.Count <= _configuration.FlushTransactionSize) { _database.PersistBatch(context, _flushingCache); } else { var actionBlock = new ActionBlockSlim <IEnumerable <KeyValuePair <ShortHash, ContentLocationEntry> > >(threads, kvs => { _database.PersistBatch(context, kvs); }); foreach (var kvs in _flushingCache.GetPages(_configuration.FlushTransactionSize)) { actionBlock.Post(kvs); } actionBlock.Complete(); actionBlock.CompletionAsync().Wait(); } } else { var actionBlock = new ActionBlockSlim <KeyValuePair <ShortHash, ContentLocationEntry> >(threads, kv => { // Do not lock on GetLock here, as it will cause a deadlock with // SetMachineExistenceAndUpdateDatabase. It is correct not do take any locks as well, because // no Store can happen while flush is running. _database.Persist(context, kv.Key, kv.Value); }); foreach (var kv in _flushingCache) { actionBlock.Post(kv); } actionBlock.Complete(); actionBlock.CompletionAsync().Wait(); } } counters[FlushableCacheCounters.Persisted].Add(_flushingCache.Count); _database.Counters[ContentLocationDatabaseCounters.NumberOfPersistedEntries].Add(_flushingCache.Count); using (counters[FlushableCacheCounters.CleanupTime].Start()) { if (_configuration.FlushPreservePercentInMemory > 0) { int targetFlushingSize = (int)(_flushingCache.Count * _configuration.FlushPreservePercentInMemory); int removeAmount = _flushingCache.Count - targetFlushingSize; foreach (var key in _flushingCache.Keys.Take(removeAmount)) { _flushingCache.RemoveKey(key); } } else { using (_exchangeLock.AcquireWriteLock()) { _flushingCache = new ConcurrentBigMap <ShortHash, ContentLocationEntry>(); } } } counters[FlushableCacheCounters.Leftover].Add(_flushingCache.Count); _database.Counters[ContentLocationDatabaseCounters.TotalNumberOfCompletedCacheFlushes].Increment(); } counters[FlushableCacheCounters.Growth].Add(_cache.Count); return(counters); }