No significant diff b/w qemux86 and qemuarm poky build of core-image-minimal

No significant diff b/w qemux86 and qemuarm poky build of core-image-minimal

[Randy MacLeod]

Khem  was asking if anyone had seen a >30% difference in build time for
qemuarm compared to other machines. I don't when building on my system:

rmacleod@yow-rmacleod-lx3 b/c-i-m-x86 $ cat x86
real    43m29.142s
user    0m19.887s
sys     0m4.110s

rmacleod@yow-rmacleod-lx3 b/c-i-m-x86 $ cat arm
real    42m58.185s
user    0m19.546s
sys     0m3.867s

This machine is relatively isolated in that there are no other users.
The arm build was done second and I didn't pre-populate the downloads
but so that may account for the 30 second difference.
I wasn't using sstate for either build.
-- 
# Randy MacLeod
# Wind River Linux

Re: No significant diff b/w qemux86 and qemuarm poky build of core-image-minimal

[Khem Raj]

On 3/30/21 10:45 AM, Randy MacLeod wrote:
> Khem  was asking if anyone had seen a >30% difference in build time for
> qemuarm compared to other machines. I don't when building on my system:
> 
> rmacleod@yow-rmacleod-lx3 b/c-i-m-x86 $ cat x86
> real    43m29.142s
> user    0m19.887s
> sys     0m4.110s
> 
> rmacleod@yow-rmacleod-lx3 b/c-i-m-x86 $ cat arm
> real    42m58.185s
> user    0m19.546s
> sys     0m3.867s
> 
> This machine is relatively isolated in that there are no other users.
> The arm build was done second and I didn't pre-populate the downloads
> but so that may account for the 30 second difference.
> I wasn't using sstate for either build.

Thanks for this infor Randy, really appreciated, I think I will also 
look at the h/w angle.

Re: [yocto] No significant diff b/w qemux86 and qemuarm poky build of core-image-minimal

[Ross Burton]

On Tue, 30 Mar 2021 at 20:41, Khem Raj <raj.khem@gmail.com> wrote:
> Thanks for this infor Randy, really appreciated, I think I will also
> look at the h/w angle.

Khem: if you can reproduce this on demand with a clean build (ie
oe-init-build-env with a clean build directory, just set DL_DIR) then
enabling buildstats would give some interesting metrics.
buildstats-diff can compare two build runs and tell you what the
differences are.

Ross

Re: [yocto] No significant diff b/w qemux86 and qemuarm poky build of core-image-minimal

[Khem Raj]

On 3/30/21 1:48 PM, Ross Burton wrote:
> On Tue, 30 Mar 2021 at 20:41, Khem Raj <raj.khem@gmail.com> wrote:
>> Thanks for this infor Randy, really appreciated, I think I will also
>> look at the h/w angle.
> 
> Khem: if you can reproduce this on demand with a clean build (ie
> oe-init-build-env with a clean build directory, just set DL_DIR) then
> enabling buildstats would give some interesting metrics.
> buildstats-diff can compare two build runs and tell you what the
> differences are.
> 

yeah this is doing world build of not only core but several other layers 
included a usual build takes around 10 hrs for this machine config, I am 
planning to

1. Collect build stats
2. buiid another qemu machine on this VM

it could very well be rotting hardware underneath the VM.

> Ross
> 

Re: [yocto] No significant diff b/w qemux86 and qemuarm poky build of core-image-minimal

[Khem Raj]

On Tue, Mar 30, 2021 at 2:20 PM Khem Raj <raj.khem@gmail.com> wrote:
>
>
>
> On 3/30/21 1:48 PM, Ross Burton wrote:
> > On Tue, 30 Mar 2021 at 20:41, Khem Raj <raj.khem@gmail.com> wrote:
> >> Thanks for this infor Randy, really appreciated, I think I will also
> >> look at the h/w angle.
> >
> > Khem: if you can reproduce this on demand with a clean build (ie
> > oe-init-build-env with a clean build directory, just set DL_DIR) then
> > enabling buildstats would give some interesting metrics.
> > buildstats-diff can compare two build runs and tell you what the
> > differences are.
> >
>
> yeah this is doing world build of not only core but several other layers
> included a usual build takes around 10 hrs for this machine config, I am
> planning to
>
> 1. Collect build stats
> 2. buiid another qemu machine on this VM
>
> it could very well be rotting hardware underneath the VM.
>

To close the loop, it turned out to be the case that CPU performance
on VM has deteriorated
which stress-ng showed. The VM has been rebuilt and everything seems
to be holding fine now.
Thanks for your help and chiming in.

> > Ross
> >