You can always click the star next to the up/down voting. =)
You should unpark cores so every core will be used.
I wanted to post an update to this older thread. Much of the older information outdated!
The current release of Unreal Engine compiles game projects extremely quickly (often as fast as a few seconds), after the first time. The first time you compile, the C++ compiler caches a ‘PreCompiled Header’ (PCH) for your game project. On subsequent compiles, the cached PCH will be used and you’ll see super-fast incremental compile times.
We are working hard on making that initial compile time faster, and you’ll see more information about this in future updates. We love hearing your feedback and please help us in our goal to have the fastest possible iteration times!
–Mike
i know its really old, but i just saw it and i have a solution for the problem the computer isn’t using its all cpu. in my case it fixed when i bought SSD and put all the source files on it. the cpu from 10% switched to 100% steady. hope it will help.
Hey, I see that it’s an old question and the four key questions have been answered. But since none of the answers above mentioned it, I’d like add that there are tools for build acceleration.
Most of the answers above will surely help you to reduce the compilation time, but you have to keep in mind that in game development, build time is a well-known problem caused mostly by the processing bottleneck, i.e, there are a lot of files to be built and build dependencies between them, so a lot of time you are waiting for a compiler to finish a job even if your CPUs aren’t busy. In that case, build acceleration will help you not only to parallelize the build process, but also to resolve redundant dependency issues.
If you are working with VC++, then IncrediBuild is probably the best tool for the job. IncrediBuild is a tool for computational processes acceleration, it is widely used by game developers and game companies, you can refer to the following link in order to see how it can help game developers, in particular Game Development Acceleration - Incredibuild .
Note that I work for IncrediBuild.
Hey Mike, does this still work? I’m getting an error that
MinFilesUsingPrecompiledHeaderOverride = 1;
bFasterWithoutUnity = true;
are unknown both unknown identifiers.
I tried putting it here:
public ProximityVoiceTarget(TargetInfo Target)
{
Type = TargetType.Game;
MinFilesUsingPrecompiledHeaderOverride = 1;
bFasterWithoutUnity = true;
}
In just a standard game project (and also tried it in the ProximityVoiceEditor.Target.cs)
ProximityVoice is just the name of my project.
I think this is outdated, we should probably use https://docs.unrealengine.com/latest/INT/Programming/UnrealBuildSystem/IWYUReferenceGuide/index.html
Yes it would be nice to hear from epic, not as in “do this” but as in “we did that” to better things.
I wait sometimes above 5 mins to compile, from 2014 to today nothing has been done with this issue. Compiling from editor if you hit compile is a nightmare.
I have 8 gb of ram and it’s not enough for the last build unreal has made for 4 before switching to 5, after a few compiles if I’m inside the editor it’s dead “memory go’s towards the limit of 7 gb” it’s done, nothing is loaded in unreal , the screen is blank in the viewport, you have been making tests and earasing them after you compile but the ram does not go back, it’s time to restart the editor 
even if it’s at half level marker it will punish you during compiling times , you are at 5 gb ram usage expect minutes.
This game engine is the only decent thing out there to write C++ in but what is the use when you do not optimize anything and just throw out new after new things that are slow, slughish a nightmare to work with. People only stick around because it offers realism with the things it has and c++ to write on the side.
There is no competition this is their problem, as soon as someone else steps in (unlike Unity that is C sharp) then watch them get their arses toghether.
Ram usage that is locked inside the system after you have cleared the working area, you do not get the ram back, useless cache that can go to 100 GB space usage fast, I understand the part if it helped , it does not, what is the use of it when things move slower and slower to load and compile . In stead of taking time to optimize the system they constantly throw out unoptimized things like Meta Humans , they are busy with this.
I asked this guy in unity, how much does it take to compile, he said 10 seconds , we are not going to move to unity because it’s C sharp anyway. But the idea …
Why make the game engine free , you made this game free for indi developers and smaller teams of devs that can create a game with more limited resources. I’m on 8 gb and it’s not enough for unreal 4 , first compilings take 1 min or less, around that, then the time grows for the rest, if I’m at 4 gb usage of ram, I can kiss goodbye one minute and say hello 2 to 3 minutes.
Why not put a button there that states in the editor “compile in this way not the other way, it will just compile this page”
We used this
MinFilesUsingPrecompiledHeaderOverride = 1;
bFasterWithoutUnity = true;
No change, and still complete unoptimal.
Well you have to do this that etc… (how about you do something EPIC and optimize the darn engine) so when I press the compiler button it only takes maximum 1 minute 