Dear all I used cachebench to test if perf works well with collecting Hardware event count and Hardware cache event count in guest. Most events' count were correct(almost as same as host), while the count of cache-refernecs, L1-dcache-load-misses, L1-icache-load-misses, dTLB-load-misses and iTLB-load-misses were much more larger than in host. Below is my test result Host Guest cache-refernecs 417555 1387017 L1-dcache-load-misses 493385 1210518 L1-icache-load-misses 1422020 4497052 dTLB-load-misses 7182 61347 iTLB-load-misses 6120 32332 my test command is "perf stat -e <event> -r 5 ./cachebench -b -x 2 -m 10 -d 3 -e 1". HostOS: kernel 3.7.2 CPU was Xeon 5620, 16 core ,48G mem GuestOS: only 1 vcpu, 8G mem and used "-cpu host" Any one has some idea with this big difference between Host and Guest will be help. Thanks -- 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