Hi,
Running your code effectively executes
@everywhere using HttpServer
This is known to generate those method redefinition warnings. The behaviour
of using in a parallel environment is a known unresolved bug. It seems like
the best syntax to use right now is
import HttpServer #Executed only on master process
@everywhere using HttpServer
For a more detailed discussion and links to the relevant issues on github
see this thread
<https://groups.google.com/forum/#!searchin/julia-users/@everywhere$20using%7Csort:relevance/julia-users/UXrv1YNbYqY/9fEyfa_ECQAJ>
.
On Friday, September 9, 2016 at 10:04:53 AM UTC-7, Adrian Salceanu wrote:
>
> Hi,
>
> I'm fumbling around with a little script with the end goal of running
> HttpServer handlers on multiple ports, in parallel, with each handler on a
> separate worker.
>
> The code looks like this:
>
> # parallel_http.jl
> using HttpServer
>
>
> function serve(port::Int)
> http = HttpHandler() do req::Request, res::Response
> Dates.now() |> string
> end
>
>
> server = Server(http)
> run(server, port)
> end
>
>
> function run_in_parallel()
> servers = Vector{RemoteRef}()
> for w in workers()
> println("About to start server on $(8000 + w)")
> push!(servers, @spawn serve(8000 + w))
> end
>
>
> servers
> end
>
>
> And in the REPL, running with julia -p 2:
>
> julia> @everywhere include("parallel_http.jl")
> WARNING: replacing module HttpServer
> WARNING: Method definition write(Base.IO, HttpCommon.Response) in module
> HttpServer at /Users/adrian/.julia/v0.4/HttpServer/src/HttpServer.jl:178
> overwritten in module HttpServer at /Users/adrian/.julia/v0.4/HttpServer/
> src/HttpServer.jl:178.
> WARNING: replacing module HttpServer
> WARNING: Method definition write(Base.IO, HttpCommon.Response) in module
> HttpServer at /Users/adrian/.julia/v0.4/HttpServer/src/HttpServer.jl:178
> overwritten in module HttpServer at /Users/adrian/.julia/v0.4/HttpServer/
> src/HttpServer.jl:178.
>
>
> julia> servers = run_in_parallel()
> About to start server on 8002
> About to start server on 8003
> 2-element Array{RemoteRef{T<:AbstractChannel},1}:
> From worker 3: Listening on 0.0.0.0:8003...
> From worker 2: Listening on 0.0.0.0:8002...
> RemoteRef{Channel{Any}}(2,1,17)
> RemoteRef{Channel{Any}}(3,1,18)
>
>
> The WARNING seems to imply that I'm doing something wrong - but if I don't
> run "using" on each worker, to avoid the warning, the module is not
> available to the worker. Am i missing something? Is there a better way to
> do this? Thanks!
>
>
