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Guy Harris (talk | contribs) →Wear-leveling and block picking: Use {{cite paper}}, so there aren't "you said web, so where's the URL" complaints due to using CiteSeerX to point to the paper. |
Guy Harris (talk | contribs) →Flash translation layer (FTL) and mapping: Naked URLs are ugly. Please drape them. Use the Wayback Machine for one link. |
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{{main|Flash file system}}
Usually, flash memory controllers also include the "flash translation layer" (FTL), a layer below the file system that maps host side or file system logical block addresses (LBAs) to the physical address of the flash memory (logical-to-physical mapping). The LBAs refer to sector numbers and to a mapping unit of 512 bytes. All LBAs that represent the logical size visible to and managed by the file system are mapped to a physical ___location (block ID, page ID and sector ID) of the Flash. As part of the [[wear leveling]] and other flash management algorithms (bad block management, read disturb management, safe flash handling etc.), the physical ___location of an LBA might dynamically change frequently. The mapping units of an FTL can differ so that LBAs are mapped block-, page- or even sub-page-based. Depending on the usage pattern, a finer mapping granularity can significantly reduce the flash wear out and maximize the endurance of a flash based storage media.<ref>{{cite web|url=http://drona.csa.iisc.ernet.in/~gopi/west10/goodson.pdf|title=Design Tradeoffs in a Flash Translation Layer|first1=Garth|last1=Goodson|first2=Rahul|last2=Iyer|archive-url=https://web.archive.org/web/20150623162937/http://drona.csa.iisc.ernet.in/~gopi/west10/goodson.pdf|archive-date=June 23, 2015}}</ref><ref>{{cite web|url=http://flashdba.com/2014/09/17/understanding-flash-the-flash-translation-layer/|title=Understanding Flash: The Flash Translation Layer|date=September 17, 2014}}</ref><ref>{{cite web|url=http://files.iccmedia.com/magazines/basfeb15/basfeb15-p25.pdf|title=New flash management architecture enables MLC for industrial storage|first=Susan|last=Heidrich|date=February 2015}}</ref>
==Garbage collection==
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