MemoryUsageSupport.h

/*
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#ifndef MemoryUsageSupport_h
#define MemoryUsageSupport_h

#include <wtf/Forward.h>
#include <wtf/text/WTFString.h>

namespace WebCore {

class MemoryUsageSupport {
public:
    // Returns the current space allocated for the pagefile, in MB.
    // That is committed size for Windows and virtual memory size for POSIX.
    static int memoryUsageMB();

    // Same as above, but always returns actual value, without any
    // caches.
    static int actualMemoryUsageMB();

    // If memory usage is below this threshold, do not bother forcing GC.
    static int lowMemoryUsageMB();

    // If memory usage is above this threshold, force GC more aggressively.
    static int highMemoryUsageMB();

    // Delta of memory usage growth (vs. last actualMemoryUsageMB())
    // to force GC when memory usage is high.
    static int highUsageDeltaMB();

    // Returns private and shared usage, in bytes. Private bytes is the amount of
    // memory currently allocated to this process that cannot be shared. Returns
    // false on platform specific error conditions.
    static bool processMemorySizesInBytes(size_t* privateBytes, size_t* sharedBytes);

    class ComponentInfo {
    public:
        ComponentInfo(const String& name, size_t size) : m_name(name), m_sizeInBytes(size) { }

        const String m_name;
        size_t m_sizeInBytes;
    };

    // Reports private memory used by components in bytes.
    static void memoryUsageByComponents(Vector<ComponentInfo>&);
};

} // namespace WebCore

#endif // MemoryUsageSupport_h