src/share/vm/utilities/globalDefinitions.hpp

Print this page 
rev 2869 : 7117303: VM uses non-monotonic time source and complains that it is non-monotonic
Summary: Replaces calls to os::javaTimeMillis(), which does not guarantee montonicity, in GC code to os::javaTimeNanos() with a suitable conversion factor. os::javaTimeNanos() mostly guarantees montonicity depending on the underlying OS implementation and, as a result, a better alternative. Changes in OS files are to make use of the newly defined constants in globalDefinitions.hpp.
Reviewed-by:


 158 
 159 const size_t K                  = 1024;
 160 const size_t M                  = K*K;
 161 const size_t G                  = M*K;
 162 const size_t HWperKB            = K / sizeof(HeapWord);
 163 
 164 const size_t LOG_K              = 10;
 165 const size_t LOG_M              = 2 * LOG_K;
 166 const size_t LOG_G              = 2 * LOG_M;
 167 
 168 const jint min_jint = (jint)1 << (sizeof(jint)*BitsPerByte-1); // 0x80000000 == smallest jint
 169 const jint max_jint = (juint)min_jint - 1;                     // 0x7FFFFFFF == largest jint
 170 
 171 // Constants for converting from a base unit to milli-base units.  For
 172 // example from seconds to milliseconds and microseconds
 173 
 174 const int MILLIUNITS    = 1000;         // milli units per base unit
 175 const int MICROUNITS    = 1000000;      // micro units per base unit
 176 const int NANOUNITS     = 1000000000;   // nano units per base unit
 177 



 178 inline const char* proper_unit_for_byte_size(size_t s) {
 179   if (s >= 10*M) {
 180     return "M";
 181   } else if (s >= 10*K) {
 182     return "K";
 183   } else {
 184     return "B";
 185   }
 186 }
 187 
 188 inline size_t byte_size_in_proper_unit(size_t s) {
 189   if (s >= 10*M) {
 190     return s/M;
 191   } else if (s >= 10*K) {
 192     return s/K;
 193   } else {
 194     return s;
 195   }
 196 }
 197 




 158 
 159 const size_t K                  = 1024;
 160 const size_t M                  = K*K;
 161 const size_t G                  = M*K;
 162 const size_t HWperKB            = K / sizeof(HeapWord);
 163 
 164 const size_t LOG_K              = 10;
 165 const size_t LOG_M              = 2 * LOG_K;
 166 const size_t LOG_G              = 2 * LOG_M;
 167 
 168 const jint min_jint = (jint)1 << (sizeof(jint)*BitsPerByte-1); // 0x80000000 == smallest jint
 169 const jint max_jint = (juint)min_jint - 1;                     // 0x7FFFFFFF == largest jint
 170 
 171 // Constants for converting from a base unit to milli-base units.  For
 172 // example from seconds to milliseconds and microseconds
 173 
 174 const int MILLIUNITS    = 1000;         // milli units per base unit
 175 const int MICROUNITS    = 1000000;      // micro units per base unit
 176 const int NANOUNITS     = 1000000000;   // nano units per base unit
 177 
 178 const jlong NANOSECS_PER_SEC      = CONST64(1000000000);
 179 const jint  NANOSECS_PER_MILLISEC = 1000000;
 180 
 181 inline const char* proper_unit_for_byte_size(size_t s) {
 182   if (s >= 10*M) {
 183     return "M";
 184   } else if (s >= 10*K) {
 185     return "K";
 186   } else {
 187     return "B";
 188   }
 189 }
 190 
 191 inline size_t byte_size_in_proper_unit(size_t s) {
 192   if (s >= 10*M) {
 193     return s/M;
 194   } else if (s >= 10*K) {
 195     return s/K;
 196   } else {
 197     return s;
 198   }
 199 }
 200