Howto: Profiling GCJ code?
Patrick Schäfer
ps@ekse.de
Tue Jun 30 18:38:00 GMT 2009
Hi,
I tried exchanging java.nio with the apache portable runtime (APR)
library which solves the issue with the garbage collector consuming
most of the time (>80%) even while being idle. But it causes the
application to spend most cycles in dynamically loading libraries at
runtime under load. I am extensively using JNA (JNI) for Posix Message
Queues and APR as transport layer which both use JNI for native
library access.
It seems to me like those libraries are dynamically loaded for every
method call. I couldn't find a way to statically bind the libraries on
mac os x. Is there a way to cache methods or any other way to improve
this?
Profile:
Self Total Library
0.0% 89.9% Unknown Library 0x696d5f74 [unreadable]
0.0% 89.8% libgcj.9.dylib _Jv_platform_dladdr(void*, _Jv_AddrInfo*)
0.0% 89.8% libSystem.B.dylib dladdr
24.2% 82.9% dyld dladdr
28.9% 28.9% dyld ImageLoaderMachO::getSymbolAddress(macho_nlist
const*, ImageLoader const*, ImageLoader::LinkContext const&) const
22.8% 22.8% dyld
ImageLoaderMachO::getIndexedExportedSymbol(unsigned int) const
6.9% 6.9% dyld
ImageLoaderMachO::getExportedSymbolAddress(ImageLoader::Symbol const*,
ImageLoader::LinkContext const&, ImageLoader const*) const
0.0% 0.0% dyld dyld::findImageContainingAddress(void const*)
0.0% 0.0% dyld ImageLoader::containsAddress(void const*) const
0.0% 0.0% dyld
ImageLoaderMachO::getExportedSymbolName(ImageLoader::Symbol const*)
const
0.0% 0.0% dyld ImageLoader::getLogicalPath() const
2.3% 2.3% dyld ImageLoaderMachO::getIndexedExportedSymbol(unsigned
int) const
2.3% 2.3% dyld
ImageLoaderMachO::getExportedSymbolAddress(ImageLoader::Symbol const*,
ImageLoader::LinkContext const&, ImageLoader const*) const
2.2% 2.2% dyld ImageLoaderMachO::getSymbolAddress(macho_nlist
const*, ImageLoader const*, ImageLoader::LinkContext const&) const
thank you for any help
patrick
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