On 12/04/16 15:50, KONRAD Frederic wrote: > > > Le 12/04/2016 14:42, Sergey Fedorov a écrit : >> On 12/04/16 14:59, Peter Maydell wrote: >>> On 12 April 2016 at 12:48, Alex Bennée <alex.ben...@linaro.org> wrote: >>>> Sergey Fedorov <serge.f...@gmail.com> writes: >>>>> Maybe we'd better use existing qemu accelerator framework and >>>>> introduce >>>>> "-machine accel=mttcg" option? >>>> My worry would be breaking existing code which assumes kvm | tcg. We >>>> will want to enable mttcg by default for combos that work without >>>> having >>>> to tweak tooling that already uses the -machine options. >>> Comments from the peanut gallery: >>> * We definitely want to just default to MTTCG where it works: >>> users shouldn't have to add new command line switches to get the >>> better performance etc, because in practice that won't happen >>> * Anything that adds a new command line option at all has to >>> be supported practically forever, so options that are only >>> useful for a transitional period are worth thinking twice about >> >> Yes, but users may like to have an option to disable MTTCG for some >> reason. I'm also concerned about icount mode: not sure how to account >> virtual time when all vCPUs run in parallel. >> >
> > I'm thinking the same, we don't have a solution for icount yet. > The reverse execution support is probably badly broken as well. Reverse execution doesn't even seem to support more than a single core. As of icount, it looks like to be incompatible with MTTCG. Kind regards, Sergey
