slow startup time of 0.3.0-rc1

[goszlanyi]

Two months ago there was a downloadable prerelease
with a really fast startup time, ~1 sec on my dual-core old laptop.

Version 0.3.0-prerelease+3082 (2014-05-17 20:09 UTC)
Commit 245782c* (64 days old master)
i686-w64-mingw32

Now the startup time is up to >6 seconds again.

Version 0.3.0-rc1+110 (2014-07-21 05:04 UTC)
Commit e5451a2 (0 days old master)
i686-w64-mingw32

Is this normal, because of some new features?
What startup time can be expected for the 0.3 release?

[tkelman]

Check the folder lib/julia. Do you see a sys.dll file? If so, you'll get fast startup but much less useful backtraces on Windows. And the sys.dll file is not typically portable across multiple machines unless you build Julia with specific options. If you had a Windows binary build in May that included sys.dll, that was probably by accident.

For Windows binary downloads of the 0.3 release, I believe the intent is to not include sys.dll because of portability and backtrace concerns. Hopefully when Julia switches to LLVM 3.5, backtraces from precompiled code can be improved on Windows too (the Rust guys landed SEH support in LLVM a few weeks ago), and this can be revisited so binary installations on Windows can also enjoy faster startup.

[goszlanyi]

You are right, the difference between fast and slow startup time is the existence of lib/julia/sys.dll.
Thank you very much for explaining the current situation.