Very long compile times in Unreal Engine Bulls & Cows 2019 version

[alexw858]

Hi all,

I’ve been working my way through the Unreal Engine C++ Developer course and have lately noticed much longer compile times than usual. I’m in section 3 (the Bull Cow game section) and I’m well past the lecture that explains how to speed up compiles by making a small change to the UnrealHeaderTool.target file (currently lecture #52). I do remember at the time, this sped up my compiles by a lot (from ~20 seconds down to ~4 or 5 seconds when compiling after a new change). Now I noticed at about lecture 70 (TArray Functions.Num()) my compile times increased all the way up to ~46 seconds. I highly doubt that this is an issue with my system specs, since I have a brand new Ryzen 7 3700x and on top of that I can see the compile times in the video lectures are much shorter. I’ve attached the compiler log output after I add a space at the end of a line in the BullCowCartridge.cpp file and recompile.

I’m hoping it’s a simple fix like what was described in the previous lecture, such as navigating to a .target file and making a change and recompiling. Has anyone else had this issue or knows what could be going on here? Thanks for reading!!

PC specs:
AMD Ryzen 7 3700x
G.Skill Trident Z Neo 32 GB DDR4 3600 memory
AMD Radeon RX 5700XT
Sabrent Rocket 1 TB PCIe 4.0 nVME drive
Windows 10 64 bit

UE4 compile log 2020-05-24|690x179

[alexw858]

I figured out which lesson is causing the long compile times. Luckily I’ve been using git via SourceTree and making commits after every lesson so diagnosing this issue was much easier. I went back in history to Lesson 68 and found the shorter compile times were back. Lesson 69 (Advanced cursor usage in VSCode) changes compile times from less than 2 seconds all the way up to 45+ seconds for me. I posted a screenshot of the compile log from lesson 68 before the compile time increase for reference. My best guess is that the list of 1000 words added during this lesson isn’t optimized well at all and is causing the slow-down. I have very recent hardware in my computer, and I saw another very similar post but their compile time was 10 minutes! I bet it was this lesson that did it for them too. Anyways I hope this helps others with this issue, and if there is a way to optimize this section (waiting almost a minute every time I want to test something can get annoying) please let me know!

[DanM]

I’ve written about moving it to runtime here

Slow compile times after adding word list on BullCowGame

You can move it to runtime by using FFileHelper and move HiddenWordList.h to the Content directory and change the file extension to txt having just the words separated by new lines i.e. a ability able about ... Then in BeginPlay #include "FIleHelper.h" #include "Paths.h" void UBullCowCartridge::BeginPlay() { Super::BeginPlay(); TArray<FString> WordList; const FString WordListPath = FPaths::ProjectContentDir() / TEXT("HiddenWordList.txt"); FFileHelper::LoadFileToStringArray(Wor…

[alexw858]

It worked, thanks a lot! I’m now down to 2.5 second compile times, much better.