| // Copyright (c) 2011 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. |
| |
| // This is the browser side of the cache manager, it tracks the activity of the |
| // render processes and allocates available memory cache resources. |
| |
| #ifndef COMPONENTS_WEB_CACHE_BROWSER_WEB_CACHE_MANAGER_H_ |
| #define COMPONENTS_WEB_CACHE_BROWSER_WEB_CACHE_MANAGER_H_ |
| |
| #include <stddef.h> |
| |
| #include <list> |
| #include <map> |
| #include <set> |
| |
| #include "base/compiler_specific.h" |
| #include "base/gtest_prod_util.h" |
| #include "base/macros.h" |
| #include "base/memory/weak_ptr.h" |
| #include "base/no_destructor.h" |
| #include "base/scoped_observer.h" |
| #include "base/time/time.h" |
| #include "components/web_cache/public/mojom/web_cache.mojom.h" |
| #include "content/public/browser/render_process_host.h" |
| #include "content/public/browser/render_process_host_creation_observer.h" |
| #include "content/public/browser/render_process_host_observer.h" |
| #include "mojo/public/cpp/bindings/remote.h" |
| |
| namespace web_cache { |
| |
| // Note: memory usage uses uint64_t because potentially the browser could be |
| // 32 bit and the renderers 64 bits. |
| class WebCacheManager : public content::RenderProcessHostCreationObserver, |
| public content::RenderProcessHostObserver { |
| friend class WebCacheManagerTest; |
| FRIEND_TEST_ALL_PREFIXES( |
| WebCacheManagerTest, |
| GatherStatsTest); |
| FRIEND_TEST_ALL_PREFIXES( |
| WebCacheManagerTest, |
| CallRemoveRendererAndObserveActivityInAnyOrderShouldNotCrashTest_1); |
| FRIEND_TEST_ALL_PREFIXES( |
| WebCacheManagerTest, |
| CallRemoveRendererAndObserveActivityInAnyOrderShouldNotCrashTest_2); |
| FRIEND_TEST_ALL_PREFIXES( |
| WebCacheManagerTest, |
| CallRemoveRendererAndObserveActivityInAnyOrderShouldNotCrashTest_3); |
| FRIEND_TEST_ALL_PREFIXES( |
| WebCacheManagerTest, |
| CallRemoveRendererAndObserveActivityInAnyOrderShouldNotCrashTest_4); |
| FRIEND_TEST_ALL_PREFIXES( |
| WebCacheManagerTest, |
| CallRemoveRendererAndObserveActivityInAnyOrderShouldNotCrashTest_5); |
| FRIEND_TEST_ALL_PREFIXES( |
| WebCacheManagerTest, |
| CallRemoveRendererAndObserveActivityInAnyOrderShouldNotCrashTest_6); |
| |
| public: |
| // Gets the singleton WebCacheManager object. The first time this method |
| // is called, a WebCacheManager object is constructed and returned. |
| // Subsequent calls will return the same object. |
| static WebCacheManager* GetInstance(); |
| |
| // When a render process is created, it registers itself with the cache |
| // manager host, causing the renderer to be allocated cache resources. |
| void Add(int renderer_id); |
| |
| // When a render process ends, it removes itself from the cache manager host, |
| // freeing the manager to assign its cache resources to other renderers. |
| void Remove(int renderer_id); |
| |
| // The cache manager assigns more cache resources to active renderer. When a |
| // renderer is active, it should inform the cache manager to receive more |
| // cache resources. |
| // |
| // When a renderer moves from being inactive to being active, the cache |
| // manager may decide to adjust its resource allocation, but it will delay |
| // the recalculation, allowing ObserveActivity to return quickly. |
| void ObserveActivity(int renderer_id); |
| |
| // Periodically, renderers should inform the cache manager of their current |
| // statistics. The more up-to-date the cache manager's statistics, the |
| // better it can allocate cache resources. |
| void ObserveStats(int renderer_id, uint64_t capacity, uint64_t size); |
| |
| // The global limit on the number of bytes in all the in-memory caches. |
| uint64_t global_size_limit() const { return global_size_limit_; } |
| |
| // Sets the global size limit, forcing a recalculation of cache allocations. |
| void SetGlobalSizeLimit(uint64_t bytes); |
| |
| // Clears all in-memory caches. |
| void ClearCache(); |
| |
| // Instantly clears renderer cache for a process. |
| // Must be called between Add(process_id) and Remove(process_id). |
| void ClearCacheForProcess(int process_id); |
| |
| // Clears all in-memory caches when a tab is reloaded or the user navigates |
| // to a different website. |
| void ClearCacheOnNavigation(); |
| |
| // content::RenderProcessHostCreationObserver: |
| void OnRenderProcessHostCreated( |
| content::RenderProcessHost* process_host) override; |
| |
| // content::RenderProcessHostObserver: |
| void RenderProcessExited( |
| content::RenderProcessHost* host, |
| const content::ChildProcessTerminationInfo& info) override; |
| void RenderProcessHostDestroyed(content::RenderProcessHost* host) override; |
| |
| // Gets the default global size limit. This interrogates system metrics to |
| // tune the default size to the current system. |
| static uint64_t GetDefaultGlobalSizeLimit(); |
| |
| protected: |
| // The amount of idle time before we consider a tab to be "inactive" |
| static const int kRendererInactiveThresholdMinutes = 5; |
| |
| // Keep track of some renderer information. |
| struct RendererInfo { |
| // The access time for this renderer. |
| base::Time access; |
| uint64_t capacity; |
| uint64_t size; |
| }; |
| |
| typedef std::map<int, RendererInfo> StatsMap; |
| |
| // An allocation is the number of bytes a specific renderer should use for |
| // its cache. |
| typedef std::pair<int,uint64_t> Allocation; |
| |
| // An allocation strategy is a list of allocations specifying the resources |
| // each renderer is permitted to consume for its cache. |
| typedef std::list<Allocation> AllocationStrategy; |
| |
| // The key is the unique id of every render process host. |
| typedef std::map<int, mojo::Remote<mojom::WebCache>> WebCacheServicesMap; |
| |
| // This class is a singleton. Do not instantiate directly. Call GetInstance() |
| // instead. |
| WebCacheManager(); |
| friend class base::NoDestructor<WebCacheManager>; |
| |
| ~WebCacheManager() override; |
| |
| // Recomputes the allocation of cache resources among the renderers. Also |
| // informs the renderers of their new allocation. |
| void ReviseAllocationStrategy(); |
| |
| // Schedules a call to ReviseAllocationStrategy after a short delay. |
| void ReviseAllocationStrategyLater(); |
| |
| // The various tactics used as part of an allocation strategy. To decide |
| // how many resources a given renderer should be allocated, we consider its |
| // usage statistics. Each tactic specifies the function that maps usage |
| // statistics to resource allocations. |
| // |
| // Determining a resource allocation strategy amounts to picking a tactic |
| // for each renderer and checking that the total memory required fits within |
| // our |global_size_limit_|. |
| enum AllocationTactic { |
| // Ignore cache statistics and divide resources equally among the given |
| // set of caches. |
| DIVIDE_EVENLY, |
| |
| // Allow each renderer to keep its current set of cached resources, with |
| // some extra allocation to store new objects. |
| KEEP_CURRENT_WITH_HEADROOM, |
| |
| // Allow each renderer to keep its current set of cached resources. |
| KEEP_CURRENT, |
| }; |
| |
| // Helper functions for devising an allocation strategy |
| |
| // Add up all the stats from the given set of renderers and place the result |
| // in the given parameters. |
| void GatherStats(const std::set<int>& renderers, |
| uint64_t* capacity, |
| uint64_t* size); |
| |
| // Get the amount of memory that would be required to implement |tactic| |
| // using the specified allocation tactic. This function defines the |
| // semantics for each of the tactics. |
| static uint64_t GetSize(AllocationTactic tactic, uint64_t size); |
| |
| // Attempt to use the specified tactics to compute an allocation strategy |
| // and place the result in |strategy|. |active_stats| and |inactive_stats| |
| // are the aggregate statistics for |active_renderers_| and |
| // |inactive_renderers_|, respectively. |
| // |
| // Returns |true| on success and |false| on failure. Does not modify |
| // |strategy| on failure. |
| bool AttemptTactic(AllocationTactic active_tactic, |
| uint64_t active_size, |
| AllocationTactic inactive_tactic, |
| uint64_t inactive_size, |
| AllocationStrategy* strategy); |
| |
| // For each renderer in |renderers|, computes its allocation according to |
| // |tactic| and add the result to |strategy|. Any |extra_bytes_to_allocate| |
| // is divided evenly among the renderers. |
| void AddToStrategy(const std::set<int>& renderers, |
| AllocationTactic tactic, |
| uint64_t extra_bytes_to_allocate, |
| AllocationStrategy* strategy); |
| |
| // Enact an allocation strategy by informing the renderers of their |
| // allocations according to |strategy|. |
| void EnactStrategy(const AllocationStrategy& strategy); |
| |
| enum ClearCacheOccasion { |
| // Instructs to clear the cache instantly. |
| INSTANTLY, |
| // Instructs to clear the cache when a navigation takes place (this |
| // includes reloading a tab). |
| ON_NAVIGATION |
| }; |
| |
| // Inform all |renderers| to clear their cache. |
| void ClearRendererCache(const std::set<int>& renderers, |
| ClearCacheOccasion occation); |
| |
| // Check to see if any active renderers have fallen inactive. |
| void FindInactiveRenderers(); |
| |
| // The global size limit for all in-memory caches. |
| uint64_t global_size_limit_; |
| |
| // Maps every renderer_id our most recent copy of its statistics. |
| StatsMap stats_; |
| |
| // Every renderer we think is still around is in one of these two sets. |
| // |
| // Active renderers are those renderers that have been active more recently |
| // than they have been inactive. |
| std::set<int> active_renderers_; |
| // Inactive renderers are those renderers that have been inactive more |
| // recently than they have been active. |
| std::set<int> inactive_renderers_; |
| |
| // Maps every renderer_id with its corresponding |
| // mojo::Remote<mojom::WebCache>. |
| WebCacheServicesMap web_cache_services_; |
| |
| ScopedObserver<content::RenderProcessHost, content::RenderProcessHostObserver> |
| rph_observers_{this}; |
| |
| base::WeakPtrFactory<WebCacheManager> weak_factory_{this}; |
| |
| DISALLOW_COPY_AND_ASSIGN(WebCacheManager); |
| }; |
| |
| } // namespace web_cache |
| |
| #endif // COMPONENTS_WEB_CACHE_BROWSER_WEB_CACHE_MANAGER_H_ |