1 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef NET_DISK_CACHE_EVICTION_H_ 6 #define NET_DISK_CACHE_EVICTION_H_ 7 8 #include "base/basictypes.h" 9 #include "base/compiler_specific.h" 10 #include "base/task.h" 11 #include "net/disk_cache/disk_format.h" 12 #include "net/disk_cache/rankings.h" 13 14 namespace disk_cache { 15 16 class BackendImpl; 17 class EntryImpl; 18 19 // This class implements the eviction algorithm for the cache and it is tightly 20 // integrated with BackendImpl. 21 class Eviction { 22 public: 23 Eviction() : backend_(NULL), ALLOW_THIS_IN_INITIALIZER_LIST(factory_(this)) {} 24 ~Eviction() {} 25 26 void Init(BackendImpl* backend); 27 28 // Deletes entries from the cache until the current size is below the limit. 29 // If empty is true, the whole cache will be trimmed, regardless of being in 30 // use. 31 void TrimCache(bool empty); 32 33 // Updates the ranking information for an entry. 34 void UpdateRank(EntryImpl* entry, bool modified); 35 36 // Notifications of interesting events for a given entry. 37 void OnOpenEntry(EntryImpl* entry); 38 void OnCreateEntry(EntryImpl* entry); 39 void OnDoomEntry(EntryImpl* entry); 40 void OnDestroyEntry(EntryImpl* entry); 41 42 private: 43 void PostDelayedTrim(); 44 void DelayedTrim(); 45 void ReportTrimTimes(EntryImpl* entry); 46 Rankings::List GetListForEntry(EntryImpl* entry); 47 bool EvictEntry(CacheRankingsBlock* node, bool empty); 48 49 // We'll just keep for a while a separate set of methods that implement the 50 // new eviction algorithm. This code will replace the original methods when 51 // finished. 52 void TrimCacheV2(bool empty); 53 void UpdateRankV2(EntryImpl* entry, bool modified); 54 void OnOpenEntryV2(EntryImpl* entry); 55 void OnCreateEntryV2(EntryImpl* entry); 56 void OnDoomEntryV2(EntryImpl* entry); 57 void OnDestroyEntryV2(EntryImpl* entry); 58 Rankings::List GetListForEntryV2(EntryImpl* entry); 59 void TrimDeleted(bool empty); 60 bool RemoveDeletedNode(CacheRankingsBlock* node); 61 62 bool NodeIsOldEnough(CacheRankingsBlock* node, int list); 63 int SelectListByLenght(); 64 void ReportListStats(); 65 66 BackendImpl* backend_; 67 Rankings* rankings_; 68 IndexHeader* header_; 69 int max_size_; 70 bool new_eviction_; 71 bool first_trim_; 72 bool trimming_; 73 bool delay_trim_; 74 ScopedRunnableMethodFactory<Eviction> factory_; 75 76 DISALLOW_COPY_AND_ASSIGN(Eviction); 77 }; 78 79 } // namespace disk_cache 80 81 #endif // NET_DISK_CACHE_EVICTION_H_ 82
