base: Increase emulated discardable memory limit.

base/memory/discardable_memory_manager.cc

 // Copyright 2014 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 "base/memory/discardable_memory_manager.h"
 
 #include "base/bind.h"
 #include "base/containers/hash_tables.h"
 #include "base/containers/mru_cache.h"
 #include "base/debug/trace_event.h"
 #include "base/synchronization/lock.h"
 
 namespace base {
 namespace internal {
 namespace {
 
-// This is admittedly pretty magical. It's approximately enough memory for four
+// This is admittedly pretty magical. It's approximately enough memory for eight
 // 2560x1600 images.
-static const size_t kDefaultMemoryLimit = 64 * 1024 * 1024;
-static const size_t kDefaultBytesToKeepUnderModeratePressure =
-    kDefaultMemoryLimit / 4;
+static const size_t kDefaultMemoryLimit = 128 * 1024 * 1024;
+static const size_t kDefaultBytesToKeepUnderModeratePressure = 12 * 1024 * 1024;
 
 }  // namespace
 
 DiscardableMemoryManager::DiscardableMemoryManager()
     : allocations_(AllocationMap::NO_AUTO_EVICT),
       bytes_allocated_(0),
       memory_limit_(kDefaultMemoryLimit),
       bytes_to_keep_under_moderate_pressure_(
           kDefaultBytesToKeepUnderModeratePressure) {
   BytesAllocatedChanged();
@@ skipping 185 matching lines @@
 void DiscardableMemoryManager::EnforcePolicyWithLockAcquired() {
   PurgeLRUWithLockAcquiredUntilUsageIsWithin(memory_limit_);
 }
 
 void DiscardableMemoryManager::BytesAllocatedChanged() const {
   TRACE_COUNTER_ID1("base", "DiscardableMemoryUsage", this, bytes_allocated_);
 }
 
 }  // namespace internal
 }  // namespace base