Re: [Autotest] [KVM-AUTOTEST PATCH 15/17] KVM test: add timedrift test to kvm_tests.cfg.sample

[Marcelo Tosatti <mtosatti@redhat.com>]

On Tue, Jul 21, 2009 at 06:41:09AM -0400, Michael Goldish wrote:
> 
> ----- "Dor Laor" <dlaor@redhat.com> wrote:
> 
> > On 07/20/2009 06:07 PM, Michael Goldish wrote:
> > > Currently the test will only run on Windows.
> > > It should be able to run on Linux just as well, but if I understand
> > correctly,
> > > testing time drift on Linux is less interesting.
> > 
> > Linux is interesting too. The problem is more visible on windows
> > since
> > it uses 1000hz frequency when it plays multimedia. It makes timer irq
> > injection harder.
> 
> If I understand correctly, most Linuxes don't use RTC at all (please
> correct me if I'm wrong). This means there's no point in testing
> time drift on Linux, because even if there's any drift, it won't get
> corrected by -rtc-td-hack. And it's pretty hard to get a drift on
> RHEL-3.9 for example -- at least it was very hard for me.

https://bugzilla.redhat.com/show_bug.cgi?id=507834 for example.

Also we'd like to test different clocks. For example with RHEL5 you can
choose, via a kernel boot parameter the following clocks:

        clock=          [BUGS=IA-32, HW] gettimeofday clocksource override.
                        [Deprecated]
                        Forces specified clocksource (if avaliable) to be used
                        when calculating gettimeofday(). If specified
                        clocksource is not avalible, it defaults to PIT.
                        Format: { pit | tsc | cyclone | pmtmr }

>From Documentation/kernel-parameters.txt file of the 2.6.18 kernel.

Passing options to the guest kernel is also required for other things,
and perhaps there should be a generic mechanism to do it.

> > Does the test fail without the rtc-td-hack?
> 
> The problem with the test is that it's hard to decide on the drift
> thresholds for failure, because the more load you use, the larger the
> drift you get.
> -rtc-td-hack makes it harder to get a drift -- you need to add more load
> in order to get the same drift.
> However, in my experiments, when I got a drift, it was not corrected when
> the load stopped. If I get 5 seconds of drift during load, and then I
> stop the load and wait, the drift remains 5 seconds, which makes me think
> I may be doing something wrong. I never got to see the cool fast rotating
> clock either.
> Another weird thing I noticed was that the drift was much larger when the
> VM and load were NOT pinned to a single CPU. It could cause a leap from 5%
> to 30%. (my office desktop has 2 CPUs.)
> I used Vista with kvm-85 I think. I tried both video load (VLC) and dir /s.
> Even if I did something wrong, I hope the test itself is OK, because its
> behavior is completely configurable.
> 
> > >
> > > Also make some tiny cosmetic changes (spacing), and move the
> > stress_boot test
> > > before the shutdown test (shutdown should be last).
> > >
> > > Signed-off-by: Michael Goldish<mgoldish@redhat.com>
> > > ---
> > >   client/tests/kvm/kvm_tests.cfg.sample |   46
> > ++++++++++++++++++++++++++------
> > >   1 files changed, 37 insertions(+), 9 deletions(-)
> > >
> > > diff --git a/client/tests/kvm/kvm_tests.cfg.sample
> > b/client/tests/kvm/kvm_tests.cfg.sample
> > > index 1288952..2d75a66 100644
> > > --- a/client/tests/kvm/kvm_tests.cfg.sample
> > > +++ b/client/tests/kvm/kvm_tests.cfg.sample
> > > @@ -92,20 +92,33 @@ variants:
> > >                   test_name = disktest
> > >                   test_control_file = disktest.control
> > >
> > > -    - linux_s3:      install setup
> > > +    - linux_s3:     install setup
> > >           type = linux_s3
> > >
> > > -    - shutdown:      install setup
> > > +    - timedrift:    install setup
> > > +        type = timedrift
> > > +        extra_params += " -rtc-td-hack"
> > > +        # Pin the VM and host load to CPU #0
> > > +        cpu_mask = 0x1
> > > +        # Set the load and rest durations
> > > +        load_duration = 20
> > > +        rest_duration = 20
> > > +        # Fail if the drift after load is higher than 50%
> > > +        drift_threshold = 50
> > > +        # Fail if the drift after the rest period is higher than
> > 10%
> > > +        drift_threshold_after_rest = 10
> > > +
> > > +    - stress_boot:  install setup
> > > +        type = stress_boot
> > > +        max_vms = 5
> > > +        alive_test_cmd = ps aux
> > > +
> > > +    - shutdown:     install setup
> > >           type = shutdown
> > >           kill_vm = yes
> > >           kill_vm_gracefully = no
> > >
> > >
> > > -    - stress_boot:
> > > -        type = stress_boot
> > > -        max_vms = 5
> > > -        alive_test_cmd = ps aux
> > > -
> > >   # NICs
> > >   variants:
> > >       - @rtl8139:
> > > @@ -121,6 +134,7 @@ variants:
> > >   variants:
> > >       # Linux section
> > >       - @Linux:
> > > +        no timedrift
> > >           cmd_shutdown = shutdown -h now
> > >           cmd_reboot = shutdown -r now
> > >           ssh_status_test_command = echo $?
> > > @@ -303,8 +317,6 @@ variants:
> > >                              
> > md5sum=bf4635e4a4bd3b43838e72bc8c329d55
> > >                              
> > md5sum_1m=18ecd37b639109f1b2af05cfb57dfeaf
> > >
> > > -
> > > -
> > >       # Windows section
> > >       - @Windows:
> > >           no autotest
> > > @@ -318,6 +330,21 @@ variants:
> > >               migration_test_command = ver&&  vol
> > >           stress_boot:
> > >               alive_test_cmd = systeminfo
> > > +        timedrift:
> > > +            # For this to work, the ISO should contain vlc
> > (vlc.exe) and a video (ED_1024.avi)
> > > +            cdrom = windows/vlc.iso
> > > +            time_command = "echo TIME: %date% %time%"
> > > +            time_filter_re = "(?<=TIME: \w\w\w ).{19}(?=\.\d\d)"
> > > +            time_format = "%m/%d/%Y %H:%M:%S"
> > > +            guest_load_command = 'cmd /c "d:\vlc -f --loop
> > --no-qt-privacy-ask --no-qt-system-tray d:\ED_1024.avi"'
> > > +            # Alternative guest load:
> > > +            #guest_load_command = "(dir /s&&  dir /s&&  dir /s&& 
> > dir /s)>  nul"
> > > +            guest_load_stop_command = "taskkill /F /IM vlc.exe"
> > > +            guest_load_instances = 2
> > > +            host_load_command = "bzip2 -c --best /dev/urandom> 
> > /dev/null"
> > > +            # Alternative host load:
> > > +            #host_load_command = "dd if=/dev/urandom of=/dev/null"
> > > +            host_load_instances = 8
> > >
> > >           variants:
> > >               - Win2000:
> > > @@ -582,5 +609,6 @@ variants:
> > >           only
> > qcow2.*ide.*default.*up.*Ubuntu-8.10-server.*(autotest.sleeptest)
> > >           only rtl8139
> > >
> > > +
> > >   # Choose your test list
> > >   only fc8_quick
> --
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