/** Release any free memory back to the system,
* but only if you are above a certain fraction of use of the
* total available PHYSICAL memory.
* Calling this could help the system avoid going into swap.
*
* NOTE: This only works if you linked against tcmalloc.
* NOTE 2: This takes at least 0.1 ms on a Ubuntu 10.10 system, because of
* the call to MemoryStats.update().
*
* @param threshold :: multiplier (0-1.0) of the amount of physical
* memory used that has to be in use before the call to
* release memory is actually called.
*/
void MemoryManagerImpl::releaseFreeMemoryIfAbove(double threshold)
{
UNUSED_ARG(threshold);
#ifdef USE_TCMALLOC
Kernel::MemoryStats mem;
mem.update();
double fraction_available = static_cast<double>(mem.availMem())
/ static_cast<double>(mem.totalMem());
if (fraction_available < (1.0 - threshold))
{
// Make TCMALLOC release memory to the system
MallocExtension::instance()->ReleaseFreeMemory();
}
#endif
}
/** Write the group labeled "data"
*
* @param bank :: name of the bank
* @param is_definition
* @return error code
*/
int SaveToSNSHistogramNexus::WriteDataGroup(std::string bank,
int is_definition) {
int dataType, dataRank, dataDimensions[NX_MAXRANK];
NXname name;
void *dataBuffer;
if (NXgetinfo(inId, &dataRank, dataDimensions, &dataType) != NX_OK)
return NX_ERROR;
// Get the rectangular detector
IComponent_const_sptr det_comp =
inputWorkspace->getInstrument()->getComponentByName(std::string(bank));
RectangularDetector_const_sptr det =
boost::dynamic_pointer_cast<const RectangularDetector>(det_comp);
if (!det) {
g_log.information()
<< "Detector '" + bank +
"' not found, or it is not a rectangular detector!\n";
// Just copy that then.
if (NXmalloc(&dataBuffer, dataRank, dataDimensions, dataType) != NX_OK)
return NX_ERROR;
if (NXgetdata(inId, dataBuffer) != NX_OK)
return NX_ERROR;
if (NXcompmakedata(outId, name, dataType, dataRank, dataDimensions,
NX_COMP_LZW, dataDimensions) != NX_OK)
return NX_ERROR;
if (NXopendata(outId, name) != NX_OK)
return NX_ERROR;
if (WriteAttributes(is_definition) != NX_OK)
return NX_ERROR;
if (NXputdata(outId, dataBuffer) != NX_OK)
return NX_ERROR;
if (NXfree(&dataBuffer) != NX_OK)
return NX_ERROR;
if (NXclosedata(outId) != NX_OK)
return NX_ERROR;
} else {
// YES it is a rectangular detector.
// --- Memory requirements ----
size_t memory_required = size_t(det->xpixels() * det->ypixels()) *
size_t(inputWorkspace->blocksize()) * 2 *
sizeof(float);
Kernel::MemoryStats mem;
mem.update();
size_t memory_available = mem.availMem() * 1024;
std::cout << "Memory available: " << memory_available / 1024 << " kb. ";
std::cout << "Memory required: " << memory_required / 1024 << " kb. ";
// Give a 50% margin of error in allocating the memory
memory_available = memory_available / 2;
if (memory_available > static_cast<size_t>(5e9))
memory_available = static_cast<size_t>(5e9);
if (memory_available < memory_required) {
// Compute how large of a slab you can still use.
int x_slab;
x_slab = static_cast<int>(
memory_available /
(det->ypixels() * inputWorkspace->blocksize() * 2 * sizeof(float)));
if (x_slab <= 0)
x_slab = 1;
// Look for a slab size that evenly divides the # of pixels.
while (x_slab > 1) {
if ((det->xpixels() % x_slab) == 0)
break;
x_slab--;
}
std::cout << "Saving in slabs of " << x_slab << " X pixels.\n";
if (this->WriteOutDataOrErrors(det, x_slab, "data", "data_errors", false,
false, is_definition, bank) != NX_OK)
return NX_ERROR;
if (this->WriteOutDataOrErrors(det, x_slab, "errors", "", true, false,
is_definition, bank) != NX_OK)
return NX_ERROR;
} else {
std::cout << "Saving in one block.\n";
if (this->WriteOutDataOrErrors(det, det->xpixels(), "data", "data_errors",
false, true, is_definition, bank) != NX_OK)
return NX_ERROR;
}
}
return NX_OK;
}