Hot Spot N. 1. [primarily Used By C/Unix Programmers, But Spreading] It Is Received Wisdom That In Most Programs, Less Than 10% Of The Code Eats 90% Of The Execution Time

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hot spot n.

1. [primarily used by C/Unix programmers, but
spreading] It is received wisdom that in most programs, less than
10% of the code eats 90% of the execution time; if one were to
graph instruction visits versus code addresses, one would typically
see a few huge spikes amidst a lot of low-level noise. Such spikes
are called `hot spots' and are good candidates for heavy
optimization or hand-hacking. The term is especially used of
tight loops and recursions in the code's central algorithm, as
opposed to (say) initial set-up costs or large but infrequent I/O
operations. See tune, bum, hand-hacking

canonical examples; WWW browsers present hypertext links as
hot spots which, when clicked on, point the browser at another
document (these are specifically called hotlinks). 4. In a
massively parallel computer with shared memory, the one location
that all 10,000 processors are trying to read or write at once
(perhaps because they are all doing a busy-wait on the same
lock). 5. More generally, any place in a hardware design that
turns into a performance bottleneck due to resource