[flukus]

Most compilers won't fsync will they? The output is likely not being written straight to disk.

It's caches all the way down.

[rbanffy]

And to max out disk bandwidth before you max out your CPU cores you need a really terrible disk.

I don't think many 8-way Xeon Platinum boxes have eMMC storage.

[MayeulC]

Well, using ramdisks will let you compare and make sure the disk isn't the bottleneck, at least.

[corty]

But all compilers will close(). Compare compile times on tmpfs and you will see an improvement.