# Addprocs() to different achitectures

**URL:** <https://discourse.julialang.org/t/addprocs-to-different-achitectures/5454>\
**Category:** General Usage\
**Created:** [August 18, 2017, 5:56pm UTC](https://discourse.julialang.org/t/addprocs-to-different-achitectures/5454 "2017-08-18T17:56:42Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![Frank\_Applin](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/frank_applin/32/1654_2.png) [@Frank\_Applin](https://discourse.julialang.org/u/Frank_Applin)\
**Post date:** [August 18, 2017, 5:56pm UTC](https://discourse.julialang.org/t/addprocs-to-different-achitectures/5454/1 "2017-08-18T17:56:42Z")

</div>

Hi,

I’m experimenting with doing remote calls to different architectures (beaglebone and Raspberry Pi). I have successfully done a remotecall\_fetch() to a UDOO x86 running Mint Linux from my Dell Optiplex 755 desktop. The Udoo and Dell both have x86 architectures. I have passwordless ssh set up on the different machines.

Here is the results of doing a remote to the Udoo x86.

julia\> addprocs([“julia-user@NODE-UDOOX86”],dir=“/home/julia-user/julia-0.6.0/bin/”)  
1-element Array{Int64,1}:  
2

julia\> remotecall\_fetch(rand,2,20)  
20-element Array{Float64,1}:  
0.483415  
0.0938163  
0.287159  
0.574149  
0.0432192  
0.842411  
0.872008  
0.413705  
0.0872259  
0.393199  
0.655173  
0.800151  
0.842092  
0.0810006  
0.753906  
0.234955  
0.738402  
0.316464  
0.856606  
0.854614

I have Julia 0.6.0 running on a Beaglebone Black, but when I try to do an addprocs() to remote access the beaglebone, here’s what I get:

julia\> addprocs([“julia-user@NODE-BBB”],dir=“/home/julia-user/julia-0.6.0/bin/”)

BoundsError(Any[Symbol, Int8, UInt8, Int16, UInt16, Int32, UInt32, Int64, UInt64, Int128, UInt128, Float16, Float32, Float64, Char, DataType, Union, UnionAll, TypeName, Tuple, Array, Expr, LineNumberNode, LabelNode, GotoNode, QuoteNode, CodeInfo, TypeVar, Core.Box, Core.MethodInstance, Module, Task, String, SimpleVector, Method, GlobalRef, SlotNumber, TypedSlot, NewvarNode, SSAValue, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, (), Bool, Any, Union{}, Core.TypeofBottom, Type, svec(), Tuple{}, false, true, nothing, :Any, :Array, :TypeVar, :Box, :Tuple, :Ptr, :return, :call, :(::), :Function, :(=), :(==), :(===), :gotoifnot, :A, :B, :C, :M, :N, :T, :S, :X, :Y, :a, :b, :c, :d, :e, :f, :g, :h, :i, :j, :k, :l, :m, :n, :o, :p, :q, :r, :s, :t, :u, :v, :w, :x, :y, :z, :add\_int, :sub\_int, :mul\_int, :add\_float, :sub\_float, :new, :mul\_float, :bitcast, :start, :done, :next, :indexed\_next, :getfield, :meta, :eq\_int, :slt\_int, :sle\_int, :ne\_int, :push\_loc, :pop\_loc, :pop, :arrayset, :arrayref, :apply\_type, :inbounds, :getindex, :setindex!, :Core, :!, :+, :Base, :static\_parameter, :convert, :colon, Symbol(“#self#”), Symbol(“#temp#”), :tuple, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32], (0,))CapturedException(BoundsError(Any[Symbol, Int8, UInt8, Int16, UInt16, Int32, UInt32, Int64, UInt64, Int128, UInt128, Float16, Float32, Float64, Char, DataType, Union, UnionAll, TypeName, Tuple, Array, Expr, LineNumberNode, LabelNode, GotoNode, QuoteNode, CodeInfo, TypeVar, Core.Box, Core.MethodInstance, Module, Task, String, SimpleVector, Method, GlobalRef, SlotNumber, TypedSlot, NewvarNode, SSAValue, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, (), Bool, Any, Union{}, Core.TypeofBottom, Type, svec(), Tuple{}, false, true, nothing, :Any, :Array, :TypeVar, :Box, :Tuple, :Ptr, :return, :call, :(::), :Function, :(=), :(==), :(===), :gotoifnot, :A, :B, :C, :M, :N, :T, :S, :X, :Y, :a, :b, :c, :d, :e, :f, :g, :h, :i, :j, :k, :l, :m, :n, :o, :p, :q, :r, :s, :t, :u, :v, :w, :x, :y, :z, :add\_int, :sub\_int, :mul\_int, :add\_float, :sub\_float, :new, :mul\_float, :bitcast, :start, :done, :next, :indexed\_next, :getfield, :meta, :eq\_int, :slt\_int, :sle\_int, :ne\_int, :push\_loc, :pop\_loc, :pop, :arrayset, :arrayref, :apply\_type, :inbounds, :getindex, :setindex!, :Core, :!, :+, :Base, :static\_parameter, :convert, :colon, Symbol(“#self#”), Symbol(“#temp#”), :tuple, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32], (0,)), Any[(handle\_deserialize(::Base.Distributed.ClusterSerializer{TCPSocket}, ::Int32) at serialize.jl:659, 1), (deserialize\_msg(::Base.Distributed.ClusterSerializer{TCPSocket}) at messages.jl:98, 1), (message\_handler\_loop(::TCPSocket, ::TCPSocket, ::Bool) at process\_messages.jl:148, 1), (process\_tcp\_streams(::TCPSocket, ::TCPSocket, ::Bool) at process\_messages.jl:118, 1), ((::Base.Distributed.##99#100{TCPSocket,TCPSocket,Bool})() at event.jl:73, 1)])  
Process(1) - Unknown remote, closing connection.  
Worker 3 terminated.  
ERROR (unhandled task failure): Version read failed. Connection closed by peer.  
Stacktrace:  
[1] process\_hdr(::TCPSocket, ::Bool) at ./distributed/process\_messages.jl:257  
[2] message\_handler\_loop(::TCPSocket, ::TCPSocket, ::Bool) at ./distributed/process\_messages.jl:143  
[3] process\_tcp\_streams(::TCPSocket, ::TCPSocket, ::Bool) at ./distributed/process\_messages.jl:118  
[4] (::Base.Distributed.##99#100{TCPSocket,TCPSocket,Bool})() at ./event.jl:73  
Master process (id 1) could not connect within 60.0 seconds.  
exiting.

The directory structures are identical on both the dev boards (BBB and Udoo x86) and I can passwordless ssh into both boards.

Does anyone have any ideas? I thought you could do this in Julia regardless of the architecture.

Frank

added: 8/18/17 14:42

I just finished trying to do the addprocs() to a Raspberry Pi 2 and got the same error as I did for the Beaglebone Black.

julia\> addprocs([“julia-user@NODE-RPI2”],dir=“/home/julia-user/julia-0.6.0/bin/”)  
BoundsError(Any[Symbol, Int8, UInt8, Int16, UInt16, Int32, UInt32, Int64, UInt64, Int128, UInt128, Float16, Float32, Float64, Char, DataType, Union, UnionAll, TypeName, Tuple, Array, Expr, LineNumberNode, LabelNode, GotoNode, QuoteNode, CodeInfo, TypeVar, Core.Box, Core.MethodInstance, Module, Task, String, SimpleVector, Method, GlobalRef, SlotNumber, TypedSlot, NewvarNode, SSAValue, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, (), Bool, Any, Union{}, Core.TypeofBottom, Type, svec(), Tuple{}, false, true, nothing, :Any, :Array, :TypeVar, :Box, :Tuple, :Ptr, :return, :call, :(::), :Function, :(=), :(==), :(===), :gotoifnot, :A, :B, :C, :M, :N, :T, :S, :X, :Y, :a, :b, :c, :d, :e, :f, :g, :h, :i, :j, :k, :l, :m, :n, :o, :p, :q, :r, :s, :t, :u, :v, :w, :x, :y, :z, :add\_int, :sub\_int, :mul\_int, :add\_float, :sub\_float, :new, :mul\_float, :bitcast, :start, :done, :next, :indexed\_next, :getfield, :meta, :eq\_int, :slt\_int, :sle\_int, :ne\_int, :push\_loc, :pop\_loc, :pop, :arrayset, :arrayref, :apply\_type, :inbounds, :getindex, :setindex!, :Core, :!, :+, :Base, :static\_parameter, :convert, :colon, Symbol(“#self#”), Symbol(“#temp#”), :tuple, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32], (0,))CapturedException(BoundsError(Any[Symbol, Int8, UInt8, Int16, UInt16, Int32, UInt32, Int64, UInt64, Int128, UInt128, Float16, Float32, Float64, Char, DataType, Union, UnionAll, TypeName, Tuple, Array, Expr, LineNumberNode, LabelNode, GotoNode, QuoteNode, CodeInfo, TypeVar, Core.Box, Core.MethodInstance, Module, Task, String, SimpleVector, Method, GlobalRef, SlotNumber, TypedSlot, NewvarNode, SSAValue, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, Symbol, (), Bool, Any, Union{}, Core.TypeofBottom, Type, svec(), Tuple{}, false, true, nothing, :Any, :Array, :TypeVar, :Box, :Tuple, :Ptr, :return, :call, :(::), :Function, :(=), :(==), :(===), :gotoifnot, :A, :B, :C, :M, :N, :T, :S, :X, :Y, :a, :b, :c, :d, :e, :f, :g, :h, :i, :j, :k, :l, :m, :n, :o, :p, :q, :r, :s, :t, :u, :v, :w, :x, :y, :z, :add\_int, :sub\_int, :mul\_int, :add\_float, :sub\_float, :new, :mul\_float, :bitcast, :start, :done, :next, :indexed\_next, :getfield, :meta, :eq\_int, :slt\_int, :sle\_int, :ne\_int, :push\_loc, :pop\_loc, :pop, :arrayset, :arrayref, :apply\_type, :inbounds, :getindex, :setindex!, :Core, :!, :+, :Base, :static\_parameter, :convert, :colon, Symbol(“#self#”), Symbol(“#temp#”), :tuple, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, :_reserved_, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32], (0,)), Any[(handle\_deserialize(::Base.Distributed.ClusterSerializer{TCPSocket}, ::Int32) at serialize.jl:659, 1), (deserialize\_msg(::Base.Distributed.ClusterSerializer{TCPSocket}) at messages.jl:98, 1), (message\_handler\_loop(::TCPSocket, ::TCPSocket, ::Bool) at process\_messages.jl:148, 1), (process\_tcp\_streams(::TCPSocket, ::TCPSocket, ::Bool) at process\_messages.jl:118, 1), ((::Base.Distributed.##99#100{TCPSocket,TCPSocket,Bool})() at event.jl:73, 1)])  
Process(1) - Unknown remote, closing connection.  
Worker 2 terminated.  
ERROR (unhandled task failure): Version read failed. Connection closed by peer.  
Stacktrace:  
[1] process\_hdr(::TCPSocket, ::Bool) at ./distributed/process\_messages.jl:257  
[2] message\_handler\_loop(::TCPSocket, ::TCPSocket, ::Bool) at ./distributed/process\_messages.jl:143  
[3] process\_tcp\_streams(::TCPSocket, ::TCPSocket, ::Bool) at ./distributed/process\_messages.jl:118  
[4] (::Base.Distributed.##99#100{TCPSocket,TCPSocket,Bool})() at ./event.jl:73  
Master process (id 1) could not connect within 60.0 seconds.  
exiting.

Here’s some info. about the RPi2:

uname -a  
Linux NODE-RPI2 4.9.35-v7+ #1014 SMP Fri Jun 30 14:47:43 BST 2017 armv7l GNU/Linux

lsb\_release -a  
No LSB modules are available.  
Distributor ID: Raspbian  
Description: Raspbian GNU/Linux 8.0 (jessie)  
Release: 8.0  
Codename: jessie

Info. for Beaglebone Black:

uname -a  
Linux NODE-BBB 4.4.80-ti-r116 #1 SMP Wed Aug 9 15:33:47 UTC 2017 armv7l GNU/Linux

lsb\_release -r  
Release: 9.1 [debian]

---

<div class="post-metadata">

**Author:** ![Frank\_Applin](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/frank_applin/32/1654_2.png) [@Frank\_Applin](https://discourse.julialang.org/u/Frank_Applin)\
**Post date:** [August 18, 2017, 7:14pm UTC](https://discourse.julialang.org/t/addprocs-to-different-achitectures/5454/2 "2017-08-18T19:14:29Z")

</div>

On a hunch, and seeing in the error message things about Uint64 and Float64 - I wondered if had to do with 32 bit versus 64 bit installations. The ARM installations were 32 bit and x86 installations were 64-bit. So, I downloaded the 32 bit version and installed on my Dell (it’s the master - so to speak). I started up the 32 bit version of Julia and here’s what I got!!

For the Raspberry Pi 2:

julia\> addprocs([“julia-user@NODE-RPI2”],dir=“/home/julia-user/julia-0.6.0/bin/”)  
1-element Array{Int32,1}:  
2

julia\> remotecall\_fetch(rand, 2, 20)  
20-element Array{Float64,1}:  
0.438085  
0.904493  
0.973361  
0.679264  
0.738671  
0.822397  
0.175776  
0.638466  
0.109121  
0.234268  
0.194145  
0.00515439  
0.46107  
0.0896276  
0.367764  
0.642768  
0.88751  
0.835329  
0.980536  
0.60624

and, the Beaglebone Black:

julia\> addprocs([“julia-user@NODE-BBB”],dir=“/home/julia-user/julia-0.6.0/bin/”)

1-element Array{Int32,1}:  
3

julia\> remotecall\_fetch(rand, 3, 20)  
20-element Array{Float64,1}:  
0.421401  
0.697546  
0.92379  
0.901786  
0.754601  
0.237044  
0.687448  
0.223037  
0.637141  
0.300794  
0.526395  
0.582173  
0.019924  
0.584588  
0.470795  
0.024546  
0.995812  
0.0406491  
0.928998  
0.922926

---

<div class="post-metadata">

**Author:** ![notinaboat](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/notinaboat/32/19302_2.png) [@notinaboat](https://discourse.julialang.org/u/notinaboat)\
**Post date:** [November 10, 2020, 9:01am UTC](https://discourse.julialang.org/t/addprocs-to-different-achitectures/5454/3 "2020-11-10T09:01:20Z")

</div>

Hi @Frank_Applin,

I have also been experimenting with cross-architecture remote calls and could not get `addprocs` to work.

In my case I’m trying to call from macOS to a Raspberry Pi Zero W.  
There is no 32-bit Julia for macOS and the Pi Zero only has a 32-bit processor, so there doesn’t seem to be an easy way to make the `Int` sizes match.

I have had some success with rolling my own simple remote call service based on `eval`.

On the Pi Zero I have:

```julia
using Sockets
using Serialization

server = listen(IPv4(0), 2020)
while true
    io = accept(server)
    @async while isopen(io)
        try
            serialize(io, eval(deserialize(io)))
        catch err
            @show err
            serialize(io, err)
        end
    end
end

```

And on the Mac I have:

```julia
using Sockets
using Serialization

macro remote(io, expr)
    @assert expr.head == :call
    f = QuoteNode(expr.args[1])
    args = expr.args[2:end]
    :(remote($io, $f, $(args...)))
end

function remote(io, f, args...)
    expr = :($f($(args...)))
    serialize(io, expr)
    deserialize(io)
end

```

Examples of running code on the Pi from the Mac:

```julia
julia> pi = connect("192.168.0.173", 2020)

julia> @remote pi read(`uname -a`, String)
"Linux raspberrypi 5.4.51+ #1333 Mon Aug 10 16:38:02 BST 2020 armv6l GNU/Linux\n"

julia> @remote pi rand(UInt, 5)
5-element Array{UInt64,1}:
 0x3d6555e980075ade
 0x28e453c8348db9dd
 0xf82d7356f2b4e2a9
 0x4ac67cf676b0188a
 0xb5fcb87edf5935bb

julia> @remote pi write("/sys/class/gpio/gpio10/direction", "out")

julia> @remote pi write("/sys/class/gpio/gpio10/value", "1")

```