Remove GetProportionalSetSize.

The concept is only well-defined on Linux, but the measurement was only
implemented and used on Windows.

Bug: 819289
Change-Id: Ie69e550019e29b473c8efcae8f3c8bbc390e737b
Reviewed-on: https://chromium-review.googlesource.com/956575Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Primiano Tucci <primiano@chromium.org>
Commit-Queue: Erik Chen <erikchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#543435}

base/process/process_metrics.h

@@ -147,9 +147,6 @@ class BASE_EXPORT ProcessMetrics {
   // usage in bytes, as per definition of WorkingSetBytes. Note that this
   // function is somewhat expensive on Windows (a few ms per process).
   bool GetWorkingSetKBytes(WorkingSetKBytes* ws_usage) const;
-  // Computes pss (proportional set size) of a process. Note that this
-  // function is somewhat expensive on Windows (a few ms per process).
-  bool GetProportionalSetSizeBytes(uint64_t* pss_bytes) const;
 
 #if defined(OS_LINUX) || defined(OS_ANDROID)
   // Resident Set Size is a Linux/Android specific memory concept. Do not

base/process/process_metrics_win.cc

@@ -219,27 +219,6 @@ bool ProcessMetrics::GetWorkingSetKBytes(WorkingSetKBytes* ws_usage) const {
   return true;
 }
 
-// This function calculates the proportional set size for a process.
-bool ProcessMetrics::GetProportionalSetSizeBytes(uint64_t* pss_bytes) const {
-  double ws_pss = 0.0;
-
-  WorkingSetInformationBuffer buffer;
-  if (!buffer.QueryPageEntries(process_.Get()))
-    return false;
-
-  size_t num_page_entries = buffer.GetPageEntryCount();
-  for (size_t i = 0; i < num_page_entries; i++) {
-    if (buffer->WorkingSetInfo[i].Shared &&
-        buffer->WorkingSetInfo[i].ShareCount > 0)
-      ws_pss += 1.0 / buffer->WorkingSetInfo[i].ShareCount;
-    else
-      ws_pss += 1.0;
-  }
-
-  *pss_bytes = static_cast<uint64_t>(ws_pss * GetPageSize());
-  return true;
-}
-
 static uint64_t FileTimeToUTC(const FILETIME& ftime) {
   LARGE_INTEGER li;
   li.LowPart = ftime.dwLowDateTime;

services/resource_coordinator/public/cpp/memory_instrumentation/os_metrics_win.cc

@@ -43,15 +43,6 @@ std::vector<mojom::VmRegionPtr> OSMetrics::GetProcessMemoryMaps(
   if (!base::win::GetLoadedModulesSnapshot(::GetCurrentProcess(), &modules))
     return maps;
 
-  auto process_metrics = base::ProcessMetrics::CreateCurrentProcessMetrics();
-  uint64_t pss_bytes = 0;
-  bool res = process_metrics->GetProportionalSetSizeBytes(&pss_bytes);
-  if (res) {
-    mojom::VmRegionPtr region = mojom::VmRegion::New();
-    region->byte_stats_proportional_resident = pss_bytes;
-    maps.push_back(std::move(region));
-  }
-
   // Query the base address for each module, and attach it to the dump.
   for (size_t i = 0; i < modules.size(); ++i) {
     wchar_t module_name[MAX_PATH];