Description of problem: With kvm_intel module inserted with enabled_ept=0, utilizing hugepage in guest encounters performance decrease compared with original 4kb page. Version-Release number of selected component (if applicable): RHEL5.6-Server-20101208.1 kvm-83-219.el5 How reproducible: always Steps to Reproduce: 1.Insert module disabling ept rmmod kvm_intel modprobe kvm_intel enable_ept=0 2.Boot guest without hugepage /usr/libexec/qemu-kvm -m 8G -smp 8 -drive file=/var/lib/libvirt/images/rhel5.6.img,cache=none,format=raw,if=virtio,boot=on,werror=stop -drive file=/root/rhel5_add.img,cache=none,format=raw,if=virtio,boot=off,werror=stop -net nic,vlan=1,macaddr=00:11:ff:33:54:55,model=virtio -net tap,vlan=1 -boot c -uuid `uuidgen` -rtc-td-hack -no-kvm-pit-reinjection -balloon none -monitor stdio -vnc :1 3.Compile kernel with 16 jobs time make -j 16 4.Mount hugetlbfs mount -t hugetlbfs none /mnt/kvm_hugepages 5.Allocate hugepages echo 5000 > /proc/sys/vm/nr_hugepages 6.Boot guest with hugepage /usr/libexec/qemu-kvm -m 8G -smp 8 -drive file=/var/lib/libvirt/images/rhel5.6.img,cache=none,format=raw,if=virtio,boot=on,werror=stop -drive file=/root/rhel5_add.img,cache=none,format=raw,if=virtio,boot=off,werror=stop -net nic,vlan=1,macaddr=00:11:ff:33:54:55,model=virtio -net tap,vlan=1 -boot c -uuid `uuidgen` -rtc-td-hack -no-kvm-pit-reinjection -balloon none -monitor stdio -vnc :1 -mem-path /mnt/kvm_hugepage/ 7.Compile kernel with 16 jobs time make -j 16 Actual results: Time elapsed with guest hugepage is longer than that without hugepage. (Detailed in Additional info) Expected results: Time elapsed with guest hugepage should be less than that without hugepage. Additional info: Environment: CPU: processor : 7 vendor_id : GenuineIntel cpu family : 6 model : 44 model name : Intel(R) Xeon(R) CPU E5620 @ 2.40GHz stepping : 2 cpu MHz : 1596.000 cache size : 12288 KB physical id : 1 siblings : 4 core id : 10 cpu cores : 4 apicid : 52 fpu : yes fpu_exception : yes cpuid level : 11 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx pdpe1gb rdtscp lm constant_tsc ida nonstop_tsc arat pni monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr sse4_1 sse4_2 popcnt lahf_lm bogomips : 4787.77 clflush size : 64 cache_alignment : 64 address sizes : 40 bits physical, 48 bits virtual power management: [8] Mem: MemTotal: 16423836 kB Guest kernel: 2.6.18-225.el5 Detailed result: +----------------------------+----------+----------+----------+ | | real | user | sys | +----------------------------+----------+----------+----------+ |EPT=1 hugepage=0 |3m30s |21m40s |3m55s | +----------------------------+----------+----------+----------+ |EPT=1 hugepage=1 |3m25s |21m14s | 3m18s | +----------------------------+----------+----------+----------+ |EPT=0 hugepage=0 |7m37s |44m5s | 14m14s| +----------------------------+----------+----------+----------+ |EPT=0 hugepage=1 |9m15s |52m1s |14m7s | +----------------------------+----------+----------+----------+ |Native Host |3m11s |20m16s |2m11s | +----------------------------+----------+----------+----------+