Re: slow guest performance with build load, looking for ideas

[Erik Jacobson <erikj@sgi.com>]

I wanted to post in to the thread the lastest test run.

Avi Kivity provided some ideas to try.  I had mixed luck.  I'd like to try
this again if we have any thoughts on the vpid/ept issue, or any other
ideas for drilling down on this.  Avi Kivity mentioned LVM in the thread.
I continued to just export the whole /dev/sdb to the guest. I'm happy to
try LVM in some form if we think it would help?

As indicated, I still had trouble locating information about ept and vpid
(see below).  Several Fedora11 packages were updated in both host and guest 
since the last run, so we're at current F11+updates.  I don't know enough
about some of these kvm settings to do much beyond what I'm told to try.

System hardware:
 * Same machines as used before, extensive system detail posted earlier in
   the thread.
 * Same Nehalem based XE270 system as before
 * Hyperthreading disabled
 * System was the same as before.  Host has 8 cores, 2 sockets, and is
   Nehalem.  (Intel(R) Xeon(R) CPU X5570  @ 2.93GHz)
 * root and workarea disks are nothing special no LVM used.
 * 8gb host memory

System Settings:
 * chkconfig ntpd off
 * service ntpd stop
 * $ cat /sys/devices/system/clocksource/clocksource0/current_clocksource
kvm-clock
 * ensured kvm_stat was available on the host
 * I could NOT find vpid and ept parameters on the host.  They weren't here:
   /sys/module/kvm_intel/parameters
   nor here
   /sys/module/kvm/parameters
   So the check for those parameters resulted in no information.
   Didn't see them elsewhere either:
   # pwd
   /sys
   # find . -name vpid -print
   # find . -name ept -print

 * Version information:
   kernel host and guest: 2.6.29.5-191.fc11.x86_64
   kvm: qemu-kvm-0.10.5-3.fc11.x86_64, qemu-system-x86-0.10.5-3.fc11.x86_64

 * Build area disk is the whole /dev/sdb drive exported to the guest.  I did 
   not use LVM.

 * Root is a raw disk image, pre-allocated

 * Host and guest are fedora11 with all current updates applied.

 * 8 cpu, 4gb memory exported to guest.

 * All disks exported virtio


I had done some stuff to set up the test including a build I didn't count.

GUEST time (make -j12&&  make -j12 modules), work area disk no cache param
--------------------------------------------------------------------------
kvm_stat output BEFORE running this test:

kvm statistics

 efer_reload                 13       0
 exits                 27145076    1142
 fpu_reload             1298729       0
 halt_exits             2152011     189
 halt_wakeup             494689     123
 host_state_reload	4998646     837
 hypercalls                   0       0
 insn_emulation        10165593     302
 insn_emulation_fail          0       0
 invlpg                       0       0
 io_exits               2096834     643
 irq_exits              6469071       8
 irq_injections         4765189     190
 irq_window              279385       0
 largepages                   0       0
 mmio_exits                   0       0
 mmu_cache_miss           18670       0
 mmu_flooded                  0       0
 mmu_pde_zapped               0       0
 mmu_pte_updated              0       0
 mmu_pte_write            10440       0
 mmu_recycled                 0       0


qemu-kvm command:
/usr/bin/qemu-kvm -M pc -m 4096 -smp 8 -name f11-test -uuid b7b4b7e4-9c07-22aa-0c95-d5c8a24176c5 -monitor pty -pidfile /var/run/libvirt/qemu//f11-test.pid -drive file=/var/lib/libvirt/images/f11-test.img,if=virtio,index=0,boot=on -drive file=/dev/sdb,if=virtio,index=1 -net nic,macaddr=54:52:00:46:48:0e,model=virtio -net user -serial pty -parallel none -usb -usbdevice tablet -vnc cct201:1 -soundhw es1370 -redir tcp:5555::22

test run timing:
real	12m36.165s
user	27m28.976s
sys	8m32.245s


kvm_stat output after this test run
kvm statistics

 efer_reload                 13       0
 exits                 47097981    2003
 fpu_reload             2168308       0
 halt_exits             3378761     301
 halt_wakeup             707171     241
 host_state_reload	7545990    1538
 hypercalls                   0       0
 insn_emulation        17809066     462
 insn_emulation_fail          0       0
 invlpg                       0       0
 io_exits               2801221    1232
 irq_exits             11959063       7
 irq_injections         8395980     304
 irq_window              531641       3
 largepages                   0       0
 mmio_exits                   0       0
 mmu_cache_miss           28419       0
 mmu_flooded                  0       0
 mmu_pde_zapped               0       0
 mmu_pte_updated              0       0
 mmu_pte_write            10440       0
 mmu_recycled              7193       0





GUEST time (make -j12&&  make -j12 modules), work area disk, cache=none
-----------------------------------------------------------------------
qemu-kvm command:
/usr/bin/qemu-kvm -M pc -m 4096 -smp 8 -name f11-test -uuid b7b4b7e4-9c07-22aa-0c95-d5c8a24176c5 -monitor pty -pidfile /var/run/libvirt/qemu//f11-test.pid -drive file=/var/lib/libvirt/images/f11-test.img,if=virtio,index=0,boot=on -drive file=/dev/sdb,if=virtio,index=1,cache=none -net nic,macaddr=54:52:00:46:48:0e,model=virtio -net user -serial pty -parallel none -usb -usbdevice tablet -vnc cct201:1 -soundhw es1370 -redir tcp:5555::22

kvm_stat output BEFORE running this test:
kvm statistics

 efer_reload                 13       0
 exits                  1384042    1097
 fpu_reload              168399       0
 halt_exits              142790     179
 halt_wakeup              60526     123
 host_state_reload	 561970     827
 hypercalls                   0       0
 insn_emulation          553390     269
 insn_emulation_fail          0       0
 invlpg                       0       0
 io_exits                390616     643
 irq_exits                42529       5
 irq_injections          165009     180
 irq_window                8618       1
 largepages                   0       0
 mmio_exits                   0       0
 mmu_cache_miss            1664       0
 mmu_flooded                  0       0
 mmu_pde_zapped               0       0
 mmu_pte_updated              0       0
 mmu_pte_write             5000       0
 mmu_recycled                 0       0


test run timing:

real	11m25.250s
user	29m43.453s
sys	8m49.591s


kvm_stat output after this test run

kvm statistics

 efer_reload                 13       0
 exits                 23320965    1095
 fpu_reload             1354712       0
 halt_exits             1510807     180
 halt_wakeup             385195     123
 host_state_reload	3541625     823
 hypercalls                   0       0
 insn_emulation         9056031     272
 insn_emulation_fail          0       0
 invlpg                       0       0
 io_exits               1318308     643
 irq_exits              5553479       0
 irq_injections         4108969     180
 irq_window              279961       0
 largepages                   0       0
 mmio_exits                   0       0
 mmu_cache_miss           14225       0
 mmu_flooded                  0       0
 mmu_pde_zapped               0       0
 mmu_pte_updated              0       0
 mmu_pte_write             5000       0
 mmu_recycled                 0       0



HOST time (make -j12&&  make -j12 modules) with no guest running
----------------------------------------------------------------
real	6m50.936s
user	29m12.051s
sys	5m50.867s