| // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "net/disk_cache/eviction.h" |
| |
| #include "base/logging.h" |
| #include "base/message_loop.h" |
| #include "base/string_util.h" |
| #include "base/time.h" |
| #include "net/disk_cache/backend_impl.h" |
| #include "net/disk_cache/entry_impl.h" |
| #include "net/disk_cache/trace.h" |
| |
| using base::Time; |
| |
| namespace { |
| |
| const int kCleanUpMargin = 1024 * 1024; |
| |
| int LowWaterAdjust(int high_water) { |
| if (high_water < kCleanUpMargin) |
| return 0; |
| |
| return high_water - kCleanUpMargin; |
| } |
| |
| } // namespace |
| |
| namespace disk_cache { |
| |
| void Eviction::Init(BackendImpl* backend) { |
| // We grab a bunch of info from the backend to make the code a little cleaner |
| // when we're actually doing work. |
| backend_ = backend; |
| rankings_ = &backend->rankings_; |
| header_ = &backend_->data_->header; |
| max_size_ = LowWaterAdjust(backend_->max_size_); |
| } |
| |
| void Eviction::TrimCache(bool empty) { |
| Trace("*** Trim Cache ***"); |
| if (backend_->disabled_) |
| return; |
| |
| Time start = Time::Now(); |
| Rankings::ScopedRankingsBlock node(rankings_); |
| Rankings::ScopedRankingsBlock next(rankings_, |
| rankings_->GetPrev(node.get(), Rankings::NO_USE)); |
| DCHECK(next.get()); |
| int target_size = empty ? 0 : max_size_; |
| int deleted = 0; |
| while (header_->num_bytes > target_size && next.get()) { |
| node.reset(next.release()); |
| next.reset(rankings_->GetPrev(node.get(), Rankings::NO_USE)); |
| if (!node->Data()->pointer || empty) { |
| // This entry is not being used by anybody. |
| EntryImpl* entry; |
| bool dirty; |
| if (backend_->NewEntry(Addr(node->Data()->contents), &entry, &dirty)) { |
| Trace("NewEntry failed on Trim 0x%x", node->address().value()); |
| continue; |
| } |
| |
| if (node->Data()->pointer) { |
| entry = EntryImpl::Update(entry); |
| } |
| ReportTrimTimes(entry); |
| entry->Doom(); |
| entry->Release(); |
| if (!empty) |
| backend_->OnEvent(Stats::TRIM_ENTRY); |
| if (++deleted == 4 && !empty) { |
| #if defined(OS_WIN) |
| MessageLoop::current()->PostTask(FROM_HERE, |
| factory_.NewRunnableMethod(&Eviction::TrimCache, false)); |
| break; |
| #endif |
| } |
| } |
| } |
| |
| UMA_HISTOGRAM_TIMES(L"DiskCache.TotalTrimTime", Time::Now() - start); |
| Trace("*** Trim Cache end ***"); |
| return; |
| } |
| |
| void Eviction::UpdateRank(EntryImpl* entry, bool modified) { |
| rankings_->UpdateRank(entry->rankings(), modified, GetListForEntry(entry)); |
| } |
| |
| void Eviction::OnOpenEntry(EntryImpl* entry) { |
| } |
| |
| void Eviction::OnCreateEntry(EntryImpl* entry) { |
| rankings_->Insert(entry->rankings(), true, GetListForEntry(entry)); |
| } |
| |
| void Eviction::OnDoomEntry(EntryImpl* entry) { |
| rankings_->Remove(entry->rankings(), GetListForEntry(entry)); |
| } |
| |
| void Eviction::OnDestroyEntry(EntryImpl* entry) { |
| } |
| |
| void Eviction::ReportTrimTimes(EntryImpl* entry) { |
| static bool first_time = true; |
| if (first_time) { |
| first_time = false; |
| std::wstring name(StringPrintf(L"DiskCache.TrimAge_%d", |
| header_->experiment)); |
| static Histogram counter(name.c_str(), 1, 10000, 50); |
| counter.SetFlags(kUmaTargetedHistogramFlag); |
| counter.Add((Time::Now() - entry->GetLastUsed()).InHours()); |
| } |
| } |
| |
| Rankings::List Eviction::GetListForEntry(EntryImpl* entry) { |
| return Rankings::NO_USE; |
| } |
| |
| } // namespace disk_cache |