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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "PHCManager.h"
#include "PHC.h"
#include "mozilla/Literals.h"
#include "mozilla/Preferences.h"
#include "mozilla/StaticPrefs_memory.h"
#include "mozilla/Telemetry.h"
#include "prsystem.h"
namespace mozilla {
using namespace phc;
static const char kPHCEnabledPref[] = "memory.phc.enabled";
static const char kPHCMinRamMBPref[] = "memory.phc.min_ram_mb";
static const char kPHCAvgDelayFirst[] = "memory.phc.avg_delay.first";
static const char kPHCAvgDelayNormal[] = "memory.phc.avg_delay.normal";
static const char kPHCAvgDelayPageRuse[] = "memory.phc.avg_delay.page_reuse";
// True if PHC has ever been enabled for this process.
static bool sWasPHCEnabled = false;
static void UpdatePHCState() {
size_t mem_size = PR_GetPhysicalMemorySize() / (1_MiB);
size_t min_mem_size = StaticPrefs::memory_phc_min_ram_mb();
// Only enable PHC if there are at least 8GB of ram. Note that we use
// 1000 bytes per kilobyte rather than 1024. Some 8GB machines will have
// slightly lower actual RAM available after some hardware devices
// reserve some.
if (StaticPrefs::memory_phc_enabled() && mem_size >= min_mem_size) {
// Set PHC probablities before enabling PHC so that the first allocation
// delay gets used.
SetPHCProbabilities(StaticPrefs::memory_phc_avg_delay_first(),
StaticPrefs::memory_phc_avg_delay_normal(),
StaticPrefs::memory_phc_avg_delay_page_reuse());
SetPHCState(Enabled);
sWasPHCEnabled = true;
} else {
SetPHCState(OnlyFree);
}
}
static void PrefChangeCallback(const char* aPrefName, void* aNull) {
MOZ_ASSERT((0 == strcmp(aPrefName, kPHCEnabledPref)) ||
(0 == strcmp(aPrefName, kPHCMinRamMBPref)) ||
(0 == strcmp(aPrefName, kPHCAvgDelayFirst)) ||
(0 == strcmp(aPrefName, kPHCAvgDelayNormal)) ||
(0 == strcmp(aPrefName, kPHCAvgDelayPageRuse)));
UpdatePHCState();
}
void InitPHCState() {
Preferences::RegisterCallback(PrefChangeCallback, kPHCEnabledPref);
Preferences::RegisterCallback(PrefChangeCallback, kPHCMinRamMBPref);
Preferences::RegisterCallback(PrefChangeCallback, kPHCAvgDelayFirst);
Preferences::RegisterCallback(PrefChangeCallback, kPHCAvgDelayNormal);
Preferences::RegisterCallback(PrefChangeCallback, kPHCAvgDelayPageRuse);
UpdatePHCState();
}
void ReportPHCTelemetry() {
if (!sWasPHCEnabled) {
return;
}
MemoryUsage usage;
PHCMemoryUsage(usage);
Accumulate(Telemetry::MEMORY_PHC_SLOP, usage.mFragmentationBytes);
PHCStats stats;
GetPHCStats(stats);
Accumulate(Telemetry::MEMORY_PHC_SLOTS_ALLOCATED, stats.mSlotsAllocated);
Accumulate(Telemetry::MEMORY_PHC_SLOTS_FREED, stats.mSlotsFreed);
// There are also slots that are unused (neither free nor allocated) they
// can be calculated by knowing the total number of slots.
}
}; // namespace mozilla