xcodebuild far slower than Xcode?

Question

Building from the command line with xcodebuild is orders of magnitude slower than building the same project, same scheme, same target from within Xcode. Does anyone know why this might be the case and how I might speed up my xcodebuild build?

I'm invoking xcodebuild as follows:

xcodebuild -scheme <SCHEME> -workspace <WORKSPACE> -configuration Debug -sdk iphonesimulator7.0 -jobs 12 build

for building on a 12-core Mac Pro. I guessed at the -jobs setting but it seems reasonable. Does anyone have any advice? Is there a way, by analyzing Xcode's build log, to tell what settings for xcodebuild most closely map to what Xcode itself is using? Thanks!

Answer 1

While this alone may not explain the slowness of xcodebuild compared to IDE, I've seen some improvements if I disable Spotlight indexing on ~/Library/Developer/Xcode/DerivedData directory.