It is not a critical issue but I feel like something is wrong with at least the default Linux build settings since the file size is way bigger than both Mac and Windows and most of this comes from the executable. This could probably be reproduced with the C++ game templates.
When packaging for Windows/Mac were you using a source version of the project or the binary version from the Launcher? This may be one cause for the difference in file size that you’re seeing as building for Linux requires a source build. You will see similar differences when building a binary project vs a source project for the same OS. I have entered a report for this difference that you can follow here: Unreal Engine Issues and Bug Tracker (UE-35067)
Hey , thanks for entering the report. I was using the source version for all builds:
Windows DevelopmentEditor target built on Windows 10 using Visual Studio 2015 Update 3
Mac DevelopmentEditor target built on macOS 10.11.6 using XCode 7.3.1
Linux Development target built on Windows 10 using CrossToolchain_Linux/v7_clang-3.7.0_ld-2.24_glibc-2.12.2.zip
Btw why exactly does it differ if you package the same project in shipping mode using different builds of the engine (binary, source)? Shouldn’t they both have the same (or very similar) optimized output?
Linux is built with debug info, so the callstacks in Shipping have filename and line number. This is a default setting because for our own needs that’s crucial, however I understand why you may not need this. Unfortunately as of now there’s no setting that could be flipped, but you can run strip manually (it’s included in the cross-toolchain too).
This was of great help to me! @dgrieshofer Thanks for asking this question (and for sharing the syntax too!). Also thanks to @RCL for the solution and for your work on Unreal Linux