title: Julia package load extremely slow in first run
body: <p>I'm using Julia 1.5.2 under Linux 5.4.0 and waited around 15 minutes for <code>Pkg.add(&quot;DifferentialEquations&quot;)</code>. Then I started the Kernel in Jupyter Notebook and ran the following code. It took terribly 1 minute to execute (the actual first time that I did this it took 225s).</p>
  <pre><code>t = time()
  using Printf
  using BenchmarkTools
  using OrdinaryDiffEq
  using Plots
  tt = time() - t
  @sprintf(&quot;It took %f seconds to import Printf, BenchmarkTools, OrdinaryDiffEq and Plots.&quot;, tt)
  # It took 58.545894 seconds to import Printf, BenchmarkTools, OrdinaryDiffEq and Plots.
  </code></pre>
  <p>Finally, I done the same as above, but for each package. This is the summary:</p>
  <pre><code>Printf:           0.004755973815917969
  BenchmarkTools:   0.06729602813720703
  Plots:            19.99405598640442
  OrdinaryDiffEq:   19.001102209091187
  </code></pre>
  <p>I know from <a href="https://github.com/JuliaLang/julia/issues/24827" rel="noreferrer">here</a> that <code>Pkg</code> was slow in the past, but I think that 15 minutes isn't a normal installing time at all. However, this is not my big problem.</p>
  <p>I know that Julia needs to compile everything everytime the Kernel is started or some package is loaded. But it obviously is not a compilation time, it's a compilation eternity.</p>
  <p>Can anyone figure out why this is so terribly slow? And, if it's normal, wouldn't it be better to provide precompiled packages to <code>Pkg</code> such as <code>numpy</code> and friends are in Python? Or at least compile forever in the first <code>using</code>?</p>
  <p>Thank you!</p>
  <hr />
  <p>My complete Platform Info:</p>
  <pre><code>Julia Version 1.5.2
  Commit 539f3ce943 (2020-09-23 23:17 UTC)
  Platform Info:
    OS: Linux (x86_64-pc-linux-gnu)
    CPU: Intel(R) Core(TM) i3-6100U CPU @ 2.30GHz
    WORD_SIZE: 64
    LIBM: libopenlibm
    LLVM: libLLVM-9.0.1 (ORCJIT, skylake)
  </code></pre>