commitLimiter.cpp

/*
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 * accompanied this code).
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 * 2 along with this work; if not, write to the Free Software Foundation,
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#include "precompiled.hpp"
#include "memory/metaspace.hpp"
#include "memory/metaspace/commitLimiter.hpp"
#include "memory/metaspaceUtils.hpp"
#include "utilities/debug.hpp"
#include "utilities/globalDefinitions.hpp"

namespace metaspace {

// Returns the size, in words, by which we may expand the metaspace committed area without:
// - _cap == 0: hitting GC threshold or the MaxMetaspaceSize
// - _cap > 0: hitting cap (this is just for testing purposes)
size_t CommitLimiter::possible_expansion_words() const {
  if (_cap > 0) { // Testing.
    assert(_cnt.get() <= _cap, "Beyond limit?");
    return _cap - _cnt.get();
  }
  assert(_cnt.get() * BytesPerWord <= MaxMetaspaceSize, "Beyond limit?");
  const size_t words_left_below_max = MaxMetaspaceSize / BytesPerWord - _cnt.get();
  const size_t words_left_below_gc_threshold = MetaspaceGC::allowed_expansion();
  return MIN2(words_left_below_max, words_left_below_gc_threshold);
}

static CommitLimiter g_global_limiter(0);

// Returns the global metaspace commit counter
CommitLimiter* CommitLimiter::globalLimiter() {
  return &g_global_limiter;
}

} // namespace metaspace