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by jacquesm 883 days ago
Yes, true, you can construct a machine on which any project you care to run is CPU bound. But meanwhile on my pretty beefy servers compiling a kernel from scratch is very much i/o bound. Maybe if I run it twice in a row after all of the caches have been prepped I can get it to be CPU bound but that's cheating, no? With enough RAM almost anything is CPU bound but that's not the normal situation. A typical laptop has 4 or 8 G of RAM and will rapidly consume all that while doing a kernel compile to the point that it's talking to the disk to a degree that it will slow down to where the CPU's are stalled.
1 comments

> Yes, true, you can construct a machine on which any project you care to run is CPU bound.

You can also construct a machine on which any project you care to run is I/O bound. Which kind of makes your comment "kernel compile is not CPU bound" kind of pointless, no?

That being said, I just downloaded kernel source on my old laptop just to do a sanity check, and it's pinning all 4 of my cores to 100%, so I don't know that to tell you. Perhaps your beefy server (with, I assume, a powerful CPU) is not a typical scenario.