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Re: [PATCH] Add tree rest of compilation timevar

Actually, I've got a more general question: do people find this timevar stuff useful in understanding compilation performance? If so, what do they find it useful for?

I find it only useful at the macro level. IE to see that PRE as a pass is taking 40 seconds, or 40% of the compilation time, or whatever.

I then go profile PRE and see what's up.
I don't consider it's resolution good enough for small compilations, of course.

Besides, turning on -ftime-report changes the compilation time so much that I'm not sure I should believe it anyway.

Darwin is the only platform i've ever seen this happen on (timevars take a significant amount of time).

I've always found it humorous that they show up on my profiles. I figure one of these days, the kernel people or libc (or whatever is the cause of the performance problem) will learn to do whatever everyone else is doing to not need 2-10% of the compilation time just manipulating timers.


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