On Fri, Oct 06, 2023 at 11:02:27PM +0200, Paolo Bonzini wrote: > > > Il ven 6 ott 2023, 20:36 Richard W.M. Jones <rjones@xxxxxxxxxx> ha scritto: > > I patched my copy of qemu to add ../configure --disable-qom-cast-debug > flag. This reduced the time taken to run two test compiles inside the > guest from [465, 467] seconds down to [445, 441] seconds, which is a > saving of about 5%. > > Or ... maybe someone knows a way to disable the debugging code when > called from particular call sites? > > > You can replace the hottest sites with just a C cast. The only one I see in the > flame graph is cpu_get_tb_cpu_state(). You're right - I'll CC you on a patch I'll send to the qemu-devel lists soon. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-top is 'top' for virtual machines. Tiny program with many powerful monitoring features, net stats, disk stats, logging, etc. http://people.redhat.com/~rjones/virt-top
