Changing OOM range to 0, 1000 and tweaking OOM algorithm.

base/process_util.h

 // 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 file/namespace contains utility functions for enumerating, ending and
 // computing statistics of processes.
 
 #ifndef BASE_PROCESS_UTIL_H_
 #define BASE_PROCESS_UTIL_H_
 #pragma once
@@ skipping 157 matching lines @@
 // Returns the path to the executable of the given process.
 BASE_EXPORT FilePath GetProcessExecutablePath(ProcessHandle process);
 
 // Parse the data found in /proc/<pid>/stat and return the sum of the
 // CPU-related ticks.  Returns -1 on parse error.
 // Exposed for testing.
 BASE_EXPORT int ParseProcStatCPU(const std::string& input);
 
 static const char kAdjustOOMScoreSwitch[] = "--adjust-oom-score";
 
-// This adjusts /proc/process/oom_adj so the Linux OOM killer will prefer
-// certain process types over others. The range for the adjustment is
-// [-17,15], with [0,15] being user accessible.
+// This adjusts /proc/<pid>/oom_score_adj so the Linux OOM killer will
+// prefer to kill certain process types over others. The range for the
+// adjustment is [-1000, 1000], with [0, 1000] being user accessible.
+// If the Linux system doesn't support the newer oom_score_adj range
+// of [0, 1000], then we revert to using the older oom_adj, and
+// translate the given value into [0, 15].  Some aliasing of values
+// may occur in that case, of course.
 BASE_EXPORT bool AdjustOOMScore(ProcessId process, int score);
 #endif
 
 #if defined(OS_POSIX)
 // Returns the ID for the parent of the given process.
 BASE_EXPORT ProcessId GetParentProcessId(ProcessHandle process);
 
 // Close all file descriptors, except those which are a destination in the
 // given multimap. Only call this function in a child process where you know
 // that there aren't any other threads.
@@ skipping 527 matching lines @@
 // instance running inside the parent.  The parent's Breakpad instance should
 // not handle the child's exceptions.  Calling RestoreDefaultExceptionHandler
 // in the child after forking will restore the standard exception handler.
 // See http://crbug.com/20371/ for more details.
 void RestoreDefaultExceptionHandler();
 #endif  // defined(OS_MACOSX)
 
 }  // namespace base
 
 #endif  // BASE_PROCESS_UTIL_H_