[LITMUS^RT] Running LITMUS-RT on ARM64

[Andrii Anisov]

Hello Björn,

On 28.08.17 19:07, Andrii Anisov wrote:
> Please see attached results of this basic experiment on my setup.
> I see the bigger task execution time stretched.
At last I've changed VCPU settings (budgeting) for the domain and now I 
see the same numbers as you baremetal. PFA.
Further I would introduce more details about my setup related to RT-Xen.

Hello Meng Xu,

The results with stretched task execution time I got on a following 
VCPUs configuration:
     root at salvator-x:/domu# xl sched-rtds -v all
     Cpupool pool-rt: sched=RTDS
     Name                                ID VCPU    Period    Budget
     litmus                               1    0     10000      4000
     litmus                               1    1     10000      4000

The results close to baremetal achieved with next configuration:
     root at salvator-x:/domu# xl sched-rtds -v all
     Cpupool pool-rt: sched=RTDS
     Name                                ID VCPU    Period    Budget
     litmus                               1    0     10000      9000
     litmus                               1    1     10000      9000

Firstly I was a bit confused about how the tasks set with utilization of 
0.55 could be ran on a VCPU with bandwidth 0.4 of PCPU. Even with the 
execution time stretching.
But yep, it should really be counted "amount of workload", not the 
execution time as rtspin now counts. And the "amount of workload" should 
be calibrated baremetal (or vcpu pinned with 1.0 bandwidth?), then 
calibration values should be applied to the experimental setup.


-- 

*Andrii Anisov*


-------------- next part --------------
A non-text attachment was scrubbed...
Name: basic1.tbz2
Type: application/x-bzip-compressed-tar
Size: 80230 bytes
Desc: not available
URL: <http://lists.litmus-rt.org/pipermail/litmus-dev/attachments/20170828/5aad4e21/attachment-0001.bin>