File indexing completed on 2025-01-05 04:46:55

 /*
  * SPDX-FileCopyrightText: 2014 Daniel Vrátil <dvratil@redhat.com>
  *
  * SPDX-License-Identifier: LGPL-2.1-or-later
  *
  */
 
 #pragma once
 
 #include <QHash>
 #include <QMutex>
 
 namespace Akonadi
 {
 namespace Server
 {
 class QueryBuilder;
 class Collection;
 
 /**
  * Provides cache for collection statistics
  *
  * Collection statistics are requested very often, so to take some load from the
  * database we cache the results until the statistics are invalidated (see
  * NotificationCollector, which takes care for invalidating the statistics).
  *
  * The cache (together with optimization of the actual SQL query) seems to
  * massively improve initial folder listing on system start (when IO and CPU loads
  * are very high).
  */
 class CollectionStatistics
 {
 public:
     struct Statistics {
         qint64 count;
         qint64 size;
         qint64 read;
     };
 
     explicit CollectionStatistics(bool prefetch = true);
     virtual ~CollectionStatistics() = default;
 
     Statistics statistics(const Collection &col);
 
     void itemAdded(const Collection &col, qint64 size, bool seen);
     void itemsSeenChanged(const Collection &col, qint64 seenCount);
 
     void invalidateCollection(const Collection &col);
 
     void expireCache();
 
 protected:
     QueryBuilder prepareGenericQuery();
 
     virtual Statistics calculateCollectionStatistics(const Collection &col);
 
     QMutex mCacheLock;
     QHash<qint64, Statistics> mCache;
 };
 
 } // namespace Server
 } // namespace Akonadi