As I already explained to this mailling list, we (AdaCore) use QEMU to run a lot of short executable (~2 secs) on many different targets. In that configuration the SMP restriction on Windows (QEMU runs only on 1 core) was not efficient on our 16 cores servers.
Few months ago I asked on this mailing list if the restriction could be removed. There was no clear answer because nobody was able to tell if it would work. We decided to give it a try. During the last months we only found one problem, it was a dead lock between the TCG and IO thread, this is fixed by the second patch. We also found that suspendThread() and resumeThread() were not synchronous on SMP systems, so we added a busy loop to wait for effective suspension. Since then, we run thousands of QEMU on our SMP Windows servers each day without any problem. And of course we greatly improve the execution time of our test-suites. Fabien Chouteau (1): Release SMP restriction on Windows Olivier Hainque (2): Check effective suspension of TCG thread Ensure good ordering of memory instruction in cpu_exec cpu-exec.c | 8 ++++++++ cpus.c | 24 ++++++++++++++++++++++-- os-win32.c | 18 ------------------ 3 files changed, 30 insertions(+), 20 deletions(-) -- 1.7.9.5
