[LTP] [PATCH v2 1/1] swapoff01: Define max_runtime 45s

[Petr Vorel]

> On Wed, Sep 4, 2024 at 5:26 PM Li Wang <liwang@redhat.com> wrote:

> > On Wed, Sep 4, 2024 at 4:53 PM Cyril Hrubis <chrubis@suse.cz> wrote:

> > > Hi!
> > > > > So yes it looks like the actual test needs some runtime defined,
> > > > > although I'm not sure how long it should be. We probably need a
> > > > > reference machine to callibrate this on. I would avoid any emulated CPU
> > > > > and choose a real hardware. I guess one of the RPis e.g. Pi Zero would
> > > > > be a good choice since they are widely available and slow by any modern
> > > > > standards.

Pi Zero is good that it's slow enough that even emulated risc-v will work.

But OTOH might be more practical to measure on RPI4 or RPI3 (maybe more of us
has RPI4 or RPI3 personally or in CI). I mean unless others have/will buy Pi
Zero you will be forced to do the reference. Also Pi Zero is slow (you need to
compile, thus I will not love to do the measurements.

Also emulated risc-v and Pi Zero will always need to set LTP_RUNTIME_MUL, right?
Or do we want to do measurements that even these will run without
LTP_RUNTIME_MUL? That would help users not having to bother, but increasing
limits for fast devices might not be a good idea.

> > > > This makes sense.

> > > So I dusted off my Pi Zero and indeed the test timeouts there as well.
> > > The ntfs filesystem takes 78s, ext2 29s, exfat 20s. So I would say that

> > I'm wondering which distribution (and kernel version) did you use on raspi-0?

Yes, 78s, ext2 29s, exfat 20s is faster, but that's due Raspberry Pi Zero using
just Broadcom BCM2835 SoC as the first generation Raspberry Pi [1] (32 bit arm).
RPI4 uses Broadcom BCM2711 SoC (64-bit quad-core).

Kind regards,
Petr

[1] https://en.wikipedia.org/wiki/Raspberry_Pi#Processor

> I ask this because we might need to consider the oldest supported systems:
> - https://linux-test-project.readthedocs.io/en/latest/users/supported_systems.html