Hi all, I've written a specialized compression utility (C++). Now I want to compare it to some general purpose compressors like gzip, bzip2 and compress. CPU time and memory consumption are the main things of interest. Therefore I tried using GNU time [1] (version 1.7). With it I get the correct CPU time, but the memory resources are always zero (%p and %M in time's format string). I tested this on Linux 2.4 & 2.6, Mac OS X and OpenBSD. Then I tried writing a simple replacement [2] which utilizes the getrusage() (via wait4()) system call. But with this, the memory resources are always zero, too. Looking into GNU time's source code, it seems that it uses the same approach, so this was a no-go. ;-) Is getrusage()/wait4() broken, or not intended to be used like this? How can I get correct memory resource usage informations of a (child) process (without changing the code of the process' applications)? Kind regards, Tassilo Footnotes: [1] http://www.gnu.org/software/time/time.html [2] http://www.uni-koblenz.de/~heimdall/rusage.c - : send the line "unsubscribe linux-c-programming" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
