You can run `llc --version` to determine the host's CPU type. You
should probably use the same llc that comes with the LLVM that Julia
is using.
The exact command is
`llc --version | awk '/Host CPU:/ { print $3; }')`
-erik
On Sat, Feb 6, 2016 at 9:50 AM, Milan Bouchet-Valat <[email protected]> wrote:
> Le vendredi 05 février 2016 à 18:24 -0800, Pavel a écrit :
>> I tried this approach using a local machine with
>> product: Intel(R) Core(TM) i7-4710MQ CPU @ 2.50GHz
>> which in my understanding belongs to the "haswell" type.
>>
>> setting
>> build_sysimg(joinpath(dirname(Libdl.dlpath("libjulia")),"sys"),
>> "haswell", "/home/juser/jimg.jl", force=true)
>>
>> resulted in
>> 'haswell' is not a recognized processor for this target (ignoring
>> processor)
> Have you looked at the output of llc -mattr=help (or usr/bin/llc
> -mattr=help from the Julia install/build directory)? If this is with
> LLVM 3.3, then it doesn't look like it supported "haswell" as a target.
> You should be able to specify "core-avx2" instead.
>
>> On the other hand, setting "native" instead, after deploying on
>> GCloud haswell-zone says that the image was precompiled for a
>> different architecture.
> By definition, "native" isn't intended to be portable, so it doesn't
> sound unexpected.
>
>
> Regards
>
>
>> On Friday, February 5, 2016 at 1:01:37 AM UTC-8, Milan Bouchet-Valat
>> wrote:
>> > Le jeudi 04 février 2016 à 17:17 -0800, Pavel a écrit :
>> > > I am deploying a CPU-intensive application on Google Cloud
>> > Compute
>> > > with Julia code running inside a Docker container. GCloud
>> > instances
>> > > have a few different CPU architectures depending on the zone.
>> > > Ideally, I would like to pre-compile Julia images (i.e.
>> > different
>> > > docker container images) for all of those architectures.
>> > >
>> > > Currently the following runs on container launch:
>> > >
>> > > include(joinpath(JULIA_HOME, Base.DATAROOTDIR, "julia",
>> > > "build_sysimg.jl"))
>> > >
>> > build_sysimg(joinpath(dirname(Libdl.dlpath("libjulia")),"sys"),
>> > > "native", "/home/juser/jimg.jl", force=true)
>> > >
>> > > so that the "native" setting pre-compiles for the CPU that these
>> > > commands are running on. That takes time and having that done at
>> > the
>> > > container image build time would save cloud runtime.
>> > >
>> > > Would it be possible to pre-compile for different CPUs on my
>> > > development machine or do I need to run the pre-compilation on
>> > those
>> > > exact CPUs? If the former is possible, what build_sysimg
>> > arguments
>> > > would help? GCloud virtual machine architectures of interest
>> > include
>> > > Sandy Bridge, Ivy Bridge, and Haswell CPU types.
>> > You should be able to build images for older architectures on a
>> > machine
>> > with a newer one, i.e. build images for Sandy Bridge and Ivy Bridge
>> > on
>> > a Haswell machine. I don't think it would work in the other
>> > direction,
>> > since some instructions wouldn't be supported and the code
>> > wouldn't
>> > run.
>> >
>> > So in your case you could replace "native" with "sandybridge",
>> > "ivybridge", "haswell", or any value from the list printed by
>> > llc -mattr=help.
>> >
>> >
>> > Regards
--
Erik Schnetter <[email protected]>
http://www.perimeterinstitute.ca/personal/eschnetter/
