// Set the initial size based on any parameters specified on the command line
void HeapSizeParameters::SetHeapParameters(unsigned minsize, unsigned maxsize, unsigned percent)
{
minHeapSize = K_to_words(minsize); // If these overflow assume the result will be zero
maxHeapSize = K_to_words(maxsize);
POLYUNSIGNED memsize = 0;
if (minHeapSize == 0 || maxHeapSize == 0)
memsize = GetPhysicalMemorySize() / sizeof(PolyWord);
// If no maximum is given default it to 80% of the physical memory.
// This allows some space for the OS and other things.
if (maxHeapSize == 0 || maxHeapSize > MAXIMUMADDRESS)
{
if (memsize == 0) maxHeapSize = MAXIMUMADDRESS;
else maxHeapSize = memsize - memsize / 5;
}
// Set the initial size to the minimum if that has been provided.
POLYUNSIGNED initialSize = minHeapSize;
if (initialSize == 0) {
// If no -H option was given set the default initial size to a quarter of the memory.
if (memsize == 0) // Unable to determine memory size so default to 64M.
initialSize = 64 * 1024 * 1024;
else initialSize = memsize / 4;
}
// Initially we divide the space equally between the major and
// minor heaps. That means that there will definitely be space
// for the first minor GC to copy its data. This division can be
// changed later on.
gMem.SetSpaceForHeap(initialSize);
gMem.SetSpaceBeforeMinorGC(initialSize/2);
lastFreeSpace = initialSize;
highWaterMark = initialSize;
if (percent == 0)
userGCRatio = 1.0 / 9.0; // Default to 10% GC to 90% application
else
userGCRatio = (float)percent / (float)(100 - percent);
predictedRatio = lastMajorGCRatio = userGCRatio;
if (debugOptions & DEBUG_HEAPSIZE)
{
Log("Heap: Initial settings: Initial heap ");
LogSize(initialSize);
Log(" minimum ");
LogSize(minHeapSize);
Log(" maximum ");
LogSize(maxHeapSize);
Log(" target ratio %f\n", userGCRatio);
}
}
void HeapSizeParameters::SetReservation(unsigned rsize)
{
gMem.SetReservation(K_to_words(rsize));
}
void HeapSizeParameters::SetReservation(POLYUNSIGNED rsize)
{
gMem.SetReservation(K_to_words(rsize));
}
// Set the initial size based on any parameters specified on the command line.
// Any of these can be zero indicating they should default.
void HeapSizeParameters::SetHeapParameters(POLYUNSIGNED minsize, POLYUNSIGNED maxsize, POLYUNSIGNED initialsize, unsigned percent)
{
minHeapSize = K_to_words(minsize); // If these overflow assume the result will be zero
maxHeapSize = K_to_words(maxsize);
POLYUNSIGNED initialSize = K_to_words(initialsize);
POLYUNSIGNED memsize = GetPhysicalMemorySize() / sizeof(PolyWord);
// If no maximum is given default it to 80% of the physical memory.
// This allows some space for the OS and other things.
if (maxHeapSize == 0 || maxHeapSize > MAXIMUMADDRESS)
{
if (memsize != 0)
maxHeapSize = memsize - memsize / 5;
else maxHeapSize = MAXIMUMADDRESS;
// But if this must not be smaller than the minimum size.
if (maxHeapSize < minHeapSize) maxHeapSize = minHeapSize;
if (maxHeapSize < initialSize) maxHeapSize = initialSize;
}
// The default minimum is zero; in practice the live data size.
// The default initial size is the minimum if that has been provided,
// otherwise 8M words. There are applications that only require a small
// heap and if we set the heap large to begin with we'll never do a
// full GC and reduce it.
if (initialSize == 0)
{
if (minHeapSize != 0)
initialSize = minHeapSize;
else initialSize = 8 * gMem.DefaultSpaceSize();
// But not more than the maximum
if (initialSize > maxHeapSize) initialSize = maxHeapSize;
}
// Together with the constraints on user settings that ensures this holds.
ASSERT(initialSize >= minHeapSize && initialSize <= maxHeapSize);
// Initially we divide the space equally between the major and
// minor heaps. That means that there will definitely be space
// for the first minor GC to copy its data. This division can be
// changed later on.
gMem.SetSpaceForHeap(initialSize);
gMem.SetSpaceBeforeMinorGC(initialSize/2);
lastFreeSpace = initialSize;
highWaterMark = initialSize;
if (percent == 0)
userGCRatio = 1.0 / 9.0; // Default to 10% GC to 90% application
else
userGCRatio = (float)percent / (float)(100 - percent);
predictedRatio = lastMajorGCRatio = userGCRatio;
if (debugOptions & DEBUG_HEAPSIZE)
{
Log("Heap: Initial settings: Initial heap ");
LogSize(initialSize);
Log(" minimum ");
LogSize(minHeapSize);
Log(" maximum ");
LogSize(maxHeapSize);
Log(" target ratio %f\n", userGCRatio);
}
}