--- old/src/share/vm/logging/logConfiguration.cpp	2016-05-03 22:43:56.084411820 +0900
+++ new/src/share/vm/logging/logConfiguration.cpp	2016-05-03 22:43:55.917412401 +0900
@@ -464,7 +464,7 @@
               " -Xlog:gc=debug:file=gc.txt:none\n"
               "\t Log messages tagged with 'gc' tag using 'debug' level to file 'gc.txt' with no decorations.\n\n"
 
-              " -Xlog:gc=trace:file=gctrace.txt:uptimemillis,pids:filecount=5,filesize=1024\n"
+              " -Xlog:gc=trace:file=gctrace.txt:uptimemillis,pids:filecount=5,filesize=1m\n"
               "\t Log messages tagged with 'gc' tag using 'trace' level to a rotating fileset of 5 files of size 1MB,\n"
               "\t using the base name 'gctrace.txt', with 'uptimemillis' and 'pid' decorations.\n\n"
 
--- old/src/share/vm/logging/logFileOutput.cpp	2016-05-03 22:43:56.791409358 +0900
+++ new/src/share/vm/logging/logFileOutput.cpp	2016-05-03 22:43:56.647409859 +0900
@@ -26,6 +26,7 @@
 #include "logging/logConfiguration.hpp"
 #include "logging/logFileOutput.hpp"
 #include "memory/allocation.inline.hpp"
+#include "runtime/arguments.hpp"
 #include "runtime/os.inline.hpp"
 #include "utilities/globalDefinitions.hpp"
 #include "utilities/defaultStream.hpp"
@@ -187,14 +188,15 @@
       }
       _file_count = static_cast<uint>(value);
     } else if (strcmp(FileSizeOptionKey, key) == 0) {
-      size_t value = parse_value(value_str);
-      if (value == SIZE_MAX || value > SIZE_MAX / K) {
+      success = Arguments::atojulong(value_str, &_rotate_size);
+      if (!success) {
+        break;
+      } else if (_rotate_size > SIZE_MAX) {
         errstream->print_cr("Invalid option: %s must be in range [0, "
-                            SIZE_FORMAT "]", FileSizeOptionKey, SIZE_MAX / K);
+                            SIZE_FORMAT "]", FileSizeOptionKey, SIZE_MAX);
         success = false;
         break;
       }
-      _rotate_size = value * K;
     } else {
       errstream->print_cr("Invalid option '%s' for log file output.", key);
       success = false;
--- old/src/share/vm/logging/logFileOutput.hpp	2016-05-03 22:43:57.514406840 +0900
+++ new/src/share/vm/logging/logFileOutput.hpp	2016-05-03 22:43:57.365407359 +0900
@@ -40,7 +40,7 @@
   static const char*  TimestampFilenamePlaceholder;
   static const char*  TimestampFormat;
   static const size_t DefaultFileCount = 5;
-  static const size_t DefaultFileSize = 20 * M;
+  static const julong DefaultFileSize = 20 * M;
   static const size_t StartTimeBufferSize = 20;
   static const size_t PidBufferSize = 21;
   static const uint   MaxRotationFileCount = 1000;
@@ -56,8 +56,8 @@
   uint  _file_count_max_digits;
 
   size_t  _archive_name_len;
-  size_t  _rotate_size;
-  size_t  _current_size;
+  julong  _rotate_size;
+  julong  _current_size;
 
   // Semaphore used for synchronizing file rotations and writes
   Semaphore _rotation_semaphore;
--- old/src/share/vm/runtime/arguments.cpp	2016-05-03 22:43:58.225404365 +0900
+++ new/src/share/vm/runtime/arguments.cpp	2016-05-03 22:43:58.065404922 +0900
@@ -778,8 +778,8 @@
   return path;
 }
 
-// Parses a memory size specification string.
-static bool atomull(const char *s, julong* result) {
+// Parses a size specification string.
+bool Arguments::atojulong(const char *s, julong* result) {
   julong n = 0;
   int args_read = 0;
   bool is_hex = false;
@@ -885,7 +885,7 @@
     return false;
   }
 
-  // Check the sign first since atomull() parses only unsigned values.
+  // Check the sign first since atojulong() parses only unsigned values.
   if (*value == '-') {
     if (!result->is_intx() && !result->is_int()) {
       return false;
@@ -893,7 +893,7 @@
     value++;
     is_neg = true;
   }
-  if (!atomull(value, &v)) {
+  if (!Arguments::atojulong(value, &v)) {
     return false;
   }
   if (result->is_int()) {
@@ -2693,12 +2693,12 @@
                             uintx* uintx_arg,
                             uintx min_size) {
 
-  // Check the sign first since atomull() parses only unsigned values.
+  // Check the sign first since atojulong() parses only unsigned values.
   bool value_is_positive = !(*value == '-');
 
   if (value_is_positive) {
     julong n;
-    bool good_return = atomull(value, &n);
+    bool good_return = atojulong(value, &n);
     if (good_return) {
       bool above_minimum = n >= min_size;
       bool value_is_too_large = n > max_uintx;
@@ -2715,7 +2715,7 @@
 Arguments::ArgsRange Arguments::parse_memory_size(const char* s,
                                                   julong* long_arg,
                                                   julong min_size) {
-  if (!atomull(s, long_arg)) return arg_unreadable;
+  if (!atojulong(s, long_arg)) return arg_unreadable;
   return check_memory_size(*long_arg, min_size);
 }
 
--- old/src/share/vm/runtime/arguments.hpp	2016-05-03 22:43:59.052401485 +0900
+++ new/src/share/vm/runtime/arguments.hpp	2016-05-03 22:43:58.911401976 +0900
@@ -729,6 +729,8 @@
   static bool copy_expand_pid(const char* src, size_t srclen, char* buf, size_t buflen);
 
   static void check_unsupported_dumping_properties() NOT_CDS_RETURN;
+
+  static bool atojulong(const char *s, julong* result);
 };
 
 // Disable options not supported in this release, with a warning if they
--- old/test/serviceability/logging/TestLogRotation.java	2016-05-03 22:43:59.649399406 +0900
+++ new/test/serviceability/logging/TestLogRotation.java	2016-05-03 22:43:59.510399890 +0900
@@ -75,7 +75,7 @@
         ArrayList<String> args = new ArrayList();
         String[] logOpts = new String[]{
             "-cp", System.getProperty("java.class.path"),
-            "-Xlog:gc=debug:" + logFileName + "::filesize=" + logFileSizeK + ",filecount=" + numberOfFiles,
+            "-Xlog:gc=debug:" + logFileName + "::filesize=" + logFileSizeK + "k,filecount=" + numberOfFiles,
             "-XX:-DisableExplicitGC", // to ensure that System.gc() works
             "-Xmx128M"};
         // System.getProperty("test.java.opts") is '' if no options is set