Il 06/10/2014 06:45, Oscar Garcia ha scritto: > > I have a host with debian 7 (intel i7 - RAM 8GB), the guest OS is also > debian. I am running a program with some threads, every thread makes a > vmexit call. Also every thread runs in a isolated vcpu. The problem is > that the program does not run fluently, it looks like that every thread > interfere with each other. This situation does not happen when > separately processes call vmexit simultaneously. The question is: there > is any restriction (any lock) that block the threads. I am not sure > maybe libc, RCU, on even Qemu and KVM? At the KVM level, _most_ VCPU ioctls can run concurrently because they only take a VCPU-level mutex. QEMU however will take a global mutex on each exit to userspace. What vmexits are these? Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html