1.1 --- a/src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp Thu Jun 10 08:27:35 2010 -0700
1.2 +++ b/src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp Fri May 07 13:14:41 2010 -0400
1.3 @@ -274,10 +274,64 @@
1.4
1.5 // </NEW PREDICTION>
1.6
1.7 + // Below, we might need to calculate the pause time target based on
1.8 + // the pause interval. When we do so we are going to give G1 maximum
1.9 + // flexibility and allow it to do pauses when it needs to. So, we'll
1.10 + // arrange that the pause interval to be pause time target + 1 to
1.11 + // ensure that a) the pause time target is maximized with respect to
1.12 + // the pause interval and b) we maintain the invariant that pause
1.13 + // time target < pause interval. If the user does not want this
1.14 + // maximum flexibility, they will have to set the pause interval
1.15 + // explicitly.
1.16 +
1.17 + // First make sure that, if either parameter is set, its value is
1.18 + // reasonable.
1.19 + if (!FLAG_IS_DEFAULT(MaxGCPauseMillis)) {
1.20 + if (MaxGCPauseMillis < 1) {
1.21 + vm_exit_during_initialization("MaxGCPauseMillis should be "
1.22 + "greater than 0");
1.23 + }
1.24 + }
1.25 + if (!FLAG_IS_DEFAULT(GCPauseIntervalMillis)) {
1.26 + if (GCPauseIntervalMillis < 1) {
1.27 + vm_exit_during_initialization("GCPauseIntervalMillis should be "
1.28 + "greater than 0");
1.29 + }
1.30 + }
1.31 +
1.32 + // Then, if the pause time target parameter was not set, set it to
1.33 + // the default value.
1.34 + if (FLAG_IS_DEFAULT(MaxGCPauseMillis)) {
1.35 + if (FLAG_IS_DEFAULT(GCPauseIntervalMillis)) {
1.36 + // The default pause time target in G1 is 200ms
1.37 + FLAG_SET_DEFAULT(MaxGCPauseMillis, 200);
1.38 + } else {
1.39 + // We do not allow the pause interval to be set without the
1.40 + // pause time target
1.41 + vm_exit_during_initialization("GCPauseIntervalMillis cannot be set "
1.42 + "without setting MaxGCPauseMillis");
1.43 + }
1.44 + }
1.45 +
1.46 + // Then, if the interval parameter was not set, set it according to
1.47 + // the pause time target (this will also deal with the case when the
1.48 + // pause time target is the default value).
1.49 + if (FLAG_IS_DEFAULT(GCPauseIntervalMillis)) {
1.50 + FLAG_SET_DEFAULT(GCPauseIntervalMillis, MaxGCPauseMillis + 1);
1.51 + }
1.52 +
1.53 + // Finally, make sure that the two parameters are consistent.
1.54 + if (MaxGCPauseMillis >= GCPauseIntervalMillis) {
1.55 + char buffer[256];
1.56 + jio_snprintf(buffer, 256,
1.57 + "MaxGCPauseMillis (%u) should be less than "
1.58 + "GCPauseIntervalMillis (%u)",
1.59 + MaxGCPauseMillis, GCPauseIntervalMillis);
1.60 + vm_exit_during_initialization(buffer);
1.61 + }
1.62 +
1.63 + double max_gc_time = (double) MaxGCPauseMillis / 1000.0;
1.64 double time_slice = (double) GCPauseIntervalMillis / 1000.0;
1.65 - double max_gc_time = (double) MaxGCPauseMillis / 1000.0;
1.66 - guarantee(max_gc_time < time_slice,
1.67 - "Max GC time should not be greater than the time slice");
1.68 _mmu_tracker = new G1MMUTrackerQueue(time_slice, max_gc_time);
1.69 _sigma = (double) G1ConfidencePercent / 100.0;
1.70
