On Wed, May 28, 2014 at 02:00:06PM +0200, Marco van de Voort wrote: > > In fact I do want the best possible stuff and not a fork. I am just > > trying to help (as I would like to use it in the said current project). > > In that case some attention points: > - help implementing and testing fine grained timings on *nix. Now it only has > a special > case for linux. > - Seems high precision is not used on anything but x86. > - Is rdtsc safe for CPUs that can vary clock of cores independently like > Core Mono? What if the process changed CPU to a different clocked core?
- The rdtsc instruction needs to be protected from out of order execution. Some people use cpuid, which is expensive. It looks like the linux kernel uses mfence or lfence/mfence depending on CPU type. _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
