hot spot

hot spot

1. an area of potential violence or political unrest

2. 

a. any local area of high temperature in a part of an engine, etc.

b. part of the inlet manifold of a paraffin engine that is heated by exhaust gases to vaporize the fuel

3. Computing a company that provides wireless access to the internet for users of portable computers or the places from which the internet can be accessed in this manner

4. Med

a. a small area on the surface of or within a body with an exceptionally high concentration of radioactivity or of some chemical or mineral considered harmful

b. a similar area that generates an abnormal amount of heat, as revealed by thermography

5. Genetics a part of a chromosome that has a tendency for mutation or recombination

hot spot

See radio-source structure.

hot spot

[′hät ‚spät]

(chemical engineering)

An area or point within a reaction system at which the temperature is appreciably higher than in the bulk of the reactor; usually locates the reaction front.

(computer science)

A word in a multiprocessor memory that several processors attempt to access simultaneously, creating a conflict or bottleneck.

(engineering)

An area in a pipeline that is subject to excessive corrosion.

(forestry)

A forest region where fires occur at frequent intervals.

(graphic arts)

A region of excessive illumination on a photo.

(cell and molecular biology)

A site in a gene at which there is an unusually high frequency of mutation.

(nucleonics)

A surface area of higher than average radioactivity.

A part of a reactor fuel surface element that has become overheated.

(physics)

A localized region with temperature higher than the surroundings.

hot spot

(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 optimisation 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.

hot spot

(2)

The active location of a cursor on a bit-map display. "Put the mouse's hot spot on the "ON" widget and click the left button."

hot spot

(3)

A screen region that is sensitive to mouse clicks, which trigger some action. Hypertext help screens are an example, in which a hot spot exists in the vicinity of any word for which additional material is available.

hot spot

(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).

hot spot

(5)

More generally, any place in a hardware design that turns into a performance bottleneck due to resource contention.