// The rate estimate is in blocks per second.
void compute_desired(size_t count,
float inter_sweep_current,
float inter_sweep_estimate,
float intra_sweep_estimate) {
// If the latest inter-sweep time is below our granularity
// of measurement, we may call in here with
// inter_sweep_current == 0. However, even for suitably small
// but non-zero inter-sweep durations, we may not trust the accuracy
// of accumulated data, since it has not been "integrated"
// (read "low-pass-filtered") long enough, and would be
// vulnerable to noisy glitches. In such cases, we
// ignore the current sample and use currently available
// historical estimates.
assert(prev_sweep() + split_births() + coal_births() // "Total Production Stock"
>= split_deaths() + coal_deaths() + (ssize_t)count, // "Current stock + depletion"
"Conservation Principle");
if (inter_sweep_current > _threshold) {
ssize_t demand = prev_sweep() - (ssize_t)count + split_births() + coal_births()
- split_deaths() - coal_deaths();
assert(demand >= 0,
err_msg("Demand (" SSIZE_FORMAT ") should be non-negative for "
PTR_FORMAT " (size=" SIZE_FORMAT ")",
demand, p2i(this), count));
// Defensive: adjust for imprecision in event counting
if (demand < 0) {
demand = 0;
}
float old_rate = _demand_rate_estimate.padded_average();
float rate = ((float)demand)/inter_sweep_current;
_demand_rate_estimate.sample(rate);
float new_rate = _demand_rate_estimate.padded_average();
ssize_t old_desired = _desired;
float delta_ise = (CMSExtrapolateSweep ? intra_sweep_estimate : 0.0);
_desired = (ssize_t)(new_rate * (inter_sweep_estimate + delta_ise));
if (PrintFLSStatistics > 1) {
gclog_or_tty->print_cr("demand: " SSIZE_FORMAT ", old_rate: %f, current_rate: %f, "
"new_rate: %f, old_desired: " SSIZE_FORMAT ", new_desired: " SSIZE_FORMAT,
demand, old_rate, rate, new_rate, old_desired, _desired);
}
}
}
void AdaptiveFreeList<FreeChunk>::print_on(outputStream* st, const char* c) const {
if (c != NULL) {
st->print("%16s", c);
} else {
st->print(SIZE_FORMAT_W(16), size());
}
st->print("\t"
SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t"
SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\n",
bfr_surp(), surplus(), desired(), prev_sweep(), before_sweep(),
count(), coal_births(), coal_deaths(), split_births(), split_deaths());
}