Is there a reason to use `top` over `perf top`?

[Elazar Leibovich]

It seems that while top lists kernel provided statistics per process which
is somewhat interesting but not all that useful, perf is really sampling
the system, and gives a real picture of who's hogging your system, which is
usually why you've started top in the first place.

Let me give a trivial example. If your system is thrashing, top will not
give you a clue about what's bothering your system. It'll show processes
coming and going from the top ten, with no apparent reason. perf top,
should show consistently a very high count on a *pageout* related kernel
function. You don't have to look at the load

Likewise, a system with fork bomb, the relevant functions should show up,
and make it clear what the root of your problem is.

While I haven't actually tried it for complicated situations, it looks like
a similar tool for windows works very well[0] (note, this is not exactly
the same situation.

Does anyone have experience with perf top? Is it really working better than
top/htop?

[0] e.g.
http://randomascii.wordpress.com/2012/09/04/windows-slowdown-investigated-and-identified/,
yes, it's not 100% the same thing, because he also recorded full stack
traces, so it's more like perf record -a, but it's pretty close, and you
can see it's working well enough even before looking at the full stacktrace.
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