I have a Julia web server running within a Docker container. Everything used to run fine with Julia 1.8.3. I’m trying to upgrade to Julia 1.9, and now it seems the server takes too much time to start when I deploy it. It runs fine locally, the server starts quickly. Looking at the remote log message…

Maybe if it is not the same hardware architecture on the server?

Great point, thanks! Well they are all x86, but my local machine Sys.CPU_NAME is tigerlake and the remote is a slightly older skylake familiy chip… I suppose this could be enough to cause a conflict?

Maybe, I don’t really know much about this. But since they cache lower level stuff in precompilation for 1.9 (iiuc) it seems like it could maybe be affected.

If you run Julia with JULIA_DEBUG=loading in the docker container you will get logs for why the caches were rejected. If it is indeed due to architecture (it could be due to other things such as bounds checking being on vs. off etc.), you can do the following: In the Dockerfile before installing/p…

Thanks for the info, I tried that but still got the pre-compilation message and the timeout as before. I’m going to try looking at the debug logs now.

The log shows lots of messages like ┌ Debug: Rejecting cache file /home/app/.julia/compiled/v1.9/MyPackageXxx/iqN7A_LVvhN.ji for MyPackageXxx [7-09790-790-7-9-789-] since pkgimage can't be loaded on this target" └ @ Base loading.jl:2706 ... I was now running without the JULIA_CPU_TARGET, will put …

I have now tried simply JULIA_CPU_TARGET=generic and still got the same thing… Are there other simple things I could try just setting up flags and variables like that?

I also saw seemingly unnecessary precompilations with Julia 1.9 as compared to 1.8.

Weird, that helped me in this case `compilecache` failed when `@everywhere using` from remote machines · Issue #48217 · JuliaLang/julia · GitHub

I wasn’t able to find a reference for JULIA_CPU_TARGET other than this issue: JULIA_CPU_TARGET flag · Issue #8198 · JuliaLang/julia · GitHub Are the valid values for JULIA_CPU_TARGET still whatever the valid architectures are for gcc --march? Is there a more Julia-focused documentation of the preco…

Seemingly unnecessary Precompilation with Julia 1.9 in a Docker container

General Usage

nrontsis June 7, 2023, 5:41pm 17

I opened an issue in Julia about this with a minimal reproducible example. This also includes a minimal example for this related issue that I mentioned before.

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Seemingly unnecessary Precompilation with Julia 1.9 in a Docker container

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