Emilio G Cota writes: > On Mon, Sep 25, 2017 at 21:03:39 +0300, Lluís Vilanova wrote: >> I know it's not exactly the same we're discussing, but the plot in [1] >> compares >> a few different ways to trace memory accesses on SPEC benchmarks: >> >> * First bar is using a Intel's tool called PIN [2]. >> * Second is calling into an instrumentation function on every executed memory >> access in QEMU. >> * Third is embedding the hot path of writing the memory access info to an >> array >> into the TCG opcode stream (more or less equivalent to supporting filtering; >> when the array is full, a user's callback is called - cold path -) >> * Fourth bar can be ignored. >> >> This was working on a much older version of instrumentation for QEMU, but I >> can >> implement something that does the first use-case point above and some >> filtering >> example (second use-case point) to see what's the performance difference. >> >> [1] https://filetea.me/n3wy9WwyCCZR72E9OWXHArHDw
> Interesting! Unfortunately, this URL gives me a 404. Ok, I've uploade it somewhere else: https://people.gso.ac.upc.edu/vilanova/mtrace.pdf There's also another one that simply counts the number of memory accesses, using the same three approaches: https://people.gso.ac.upc.edu/vilanova/mcount.pdf Cheers, Lluis
