Details of Operations
A physically indexed CPU cache is designed such that addresses in adjacent physical memory blocks take different positions ("cache lines") in the cache, but this is not the case when it comes to virtual memory; when virtually adjacent but not physically adjacent memory blocks are allocated, they could potentially both take the same position in the cache. Coloring is a technique implemented in memory management software, which solves this problem by selecting pages that do not contend with neighbor pages.
Physical memory pages are "colored" so that pages with different "colors" have different positions in CPU cache memory. When allocating sequential pages in virtual memory for processes, the kernel collects pages with different "colors" and map them to the virtual memory. In this way, sequential pages in virtual memory do not contend for the same cache line.
Read more about this topic: Cache Coloring
Famous quotes containing the words details of, details and/or operations:
“There was a time when the average reader read a novel simply for the moral he could get out of it, and however naïve that may have been, it was a good deal less naïve than some of the limited objectives he has now. Today novels are considered to be entirely concerned with the social or economic or psychological forces that they will by necessity exhibit, or with those details of daily life that are for the good novelist only means to some deeper end.”
—Flannery O’Connor (1925–1964)
“Patience is a most necessary qualification for business; many a man would rather you heard his story than granted his request. One must seem to hear the unreasonable demands of the petulant, unmoved, and the tedious details of the dull, untired. That is the least price that a man must pay for a high station.”
—Philip Dormer Stanhope, 4th Earl Chesterfield (1694–1773)
“It may seem strange that any road through such a wilderness should be passable, even in winter, when the snow is three or four feet deep, but at that season, wherever lumbering operations are actively carried on, teams are continually passing on the single track, and it becomes as smooth almost as a railway.”
—Henry David Thoreau (1817–1862)