Meta tags:

Headings (most frequently used words):

edit, memory, hierarchy, the, in, navigation, tools, contents, properties, of, technologies, examples, see, also, references, menu, personal, namespaces, views, search, contribute, print, export, other, projects, languages,

Text of the page (most frequently used words):
memory (78), the (61), storage (51), data (40), and (33), #hierarchy (31), cache (18), level (17), computer (16), from (15), for (15), file (14), disk (14), original (13), are (13), access (11), size (11), may (9), research (9), retrieved (9), tape (9), ram (9), wikipedia (8), main (8), system (8), citation (8), needed (8), this (7), edit (7), that (7), nearline (7), levels (7), best (7), speed (7), drive (7), card (7), computing (7), use (6), articles (6), architecture (6), performance (6), time (6), online (6), optical (6), dvd (6), video (6), about (5), page (5), with (5), 2009 (5), org (5), 2014 (5), core (5), hardware (5), also (5), between (5), can (5), pressure (5), offline (5), around (5), flash (5), line (5), magnetic (5), available (4), not (4), archived (4), intel (4), requires (4), cloud (4), processor (4), locality (4), one (4), registers (4), lower (4), register (4), solid (4), state (4), shared (4), each (4), digital (4), rom (4), vhs (4), record (4), dram (4), distributed (4), terms (3), non (3), languages (3), cite (3), information (3), navigation (3), history (3), unsourced (3), statements (3), september (3), 2021 (3), journal (3), software (3), algorithm (3), modern (3), programmers (3), will (3), responsible (3), caches (3), such (3), transfer (3), cpu (3), object (3), reference (3), example (3), disks (3), down (3), immediately (3), secondary (3), 128 (3), mib (3), kib (3), technologies (3), 1725 (3), disc (3), recording (3), law (3), database (3), boot (3), mobile (2), view (2), contact (2), privacy (2), policy (2), wikimedia (2), commons (2), 2022 (2), links (2), other (2), pdf (2), wikidata (2), upload (2), related (2), changes (2), tools (2), help (2), article (2), contents (2), search (2), more (2), talk (2), categories (2), contain (2), all (2), short (2), description (2), different (2), missing (2), https (2), memory_hierarchy (2), 2010 (2), ibm (2), lto (2), ultrium (2), technology (2), com (2), 2017 (2), pro (2), ssd (2), sisoftware (2), haswell (2), new (2), cnet (2), 2002 (2), based (2), references (2), communication (2), pattern (2), hierarchical (2), management (2), wall (2), buffer (2), see (2), many (2), assume (2), then (2), code (2), when (2), compilers (2), moving (2), two (2), programming (2), most (2), fast (2), waiting (2), larger (2), known (2), respectively (2), higher (2), hard (2), space (2), spinning (2), while (2), array (2), media (2), cartridges (2), loaded (2), library (2), human (2), intervention (2), but (2), 2013 (2), tertiary (2), machine (2), uniform (2), instruction (2), bytes (2), has (2), components (2), examples (2), component (2), complexity (2), properties (2), general (2), paging (2), designing (2), virtual (2), off (2), member (2), response (2), 1962 (2), delay (2), punched (2), historical (2), quantum (2), universal (2), electronic (2), holographic (2), ecram (2), cbram (2), blu (2), ray (2), videotape (2), phonograph (2), reram (2), nvram (2), cell (2), volatile (2), tube (2), 1947 (2), dual (2), ported (2), sram (2), sdram (2), bank (2), raid (2), structure (2), volume (2), dump (2), store (2), validation (2), block (2), network (2), attached (2), coherence (2), jump (2), web (2), sep (2), cookie, statement, statistics, developers, disclaimers, text, under, additional, apply, using, site, you, agree, registered, trademark, profit, organization, foundation, inc, creative, attribution, sharealike, license, was, last, edited, utc, українська, türkçe, српски, srpski, русский, português, nederlands, қазақша, עברית, bahasa, indonesia, 한국어, français, فارسی, español, deutsch, català, العربية, projects, printable, version, download, print, export, item, permanent, link, special, pages, what, here, recent, community, portal, learn, contribute, donate, random, current, events, read, views, english, namespaces, log, create, account, contributions, logged, personal, menu, hidden, cs1, errors, periodical, index, php, title, oldid, 1086513241, pearson, tony, 2018, 2015, developerworks, inside, correct, term, 2011, generationslto, storagereview, samsung, 960, nvme, review, zone, anandtech, analyzed, building, crothers, brooke, news, dissecting, top, graphics, apple, inch, macbook, www, computerhistory, timeline, museum, van, der, pas, ruud, santa, clara, california, 817, 0742, sun, microsystems, systems, pádraig, brady, multi, unitity, semiconductor, corporation, august, write, combining, toy, wing, zee, benjamin, 1986, prentice, hall, 163502, isbn, avoiding, spatial, temporal, works, fine, until, application, hits, assessed, during, refactoring, generating, executed, cause, efficiently, optimizing, through, mainly, though, directly, accessed, taking, optimal, advantage, cooperation, well, underlying, support, operating, inline, assemblers, assembly, language, program, workloads, accesses, efficiency, result, spends, much, its, idling, complete, sometimes, called, likely, overflow, small, require, slower, resulting, load, being, needing, fetched, due, fault, miss, spilling, cost, caching, bottleneck, cpus, always, spin, massive, idle, removable, automatically, must, manually, maid, some, bring, made, quickly, without, downwards, formal, distinction, tiered, 160, exabytes, consumer, 2000, terabytes, case, times, numa, gib, primary, 100, 200, 700, 144, micro, operations, fastest, possible, usually, cycle, few, thousand, number, increased, over, type, change, historically, circa, amd, bulldozer, server, location, dictates, required, prefetch, occur, predicting, where, resides, difficult, latency, bandwidth, metrics, associated, neither, them, specific, particular, ways, increase, minimising, how, far, manipulate, cmox, stretches, adding, slows, structuring, structures, useful, considered, include, bulk, mass, controller, cards, internal, there, four, major, high, considering, restrictions, capabilities, various, viewed, part, memories, which, typically, smaller, faster, than, next, highest, limit, respond, filling, signaling, activating, separates, into, since, capacity, distinguished, their, controlling, affects, architectural, design, predictions, constructs, involving, 1971, floppy, 1970, bubble, 1968, twistor, pack, thin, film, 1960s, rope, 1957, plated, wire, 1949, 1932, drum, plugboard, paper, ultraram, crystal, dna, holography, patterned, millipede, nram, racetrack, development, worm, versatile, ultra, minidvd, hyper, nintendo, discs, mini, super, cdda, compact, audio, laserdisc, matic, micromv, minidv, format, betamax, linear, open, cassette, videocassette, dds, vision, apparatus, quadruplex, cylinder, analog, fefet, feram, early, stage, nano, electrochemical, mram, xpoint, pcm, memristor, memistor, programmable, metallization, xqd, microp2, sxs, smartmedia, sim, multimediacard, compactflash, stick, sss, module, flashsystem, usb, sshd, hybrid, used, cartridge, eeprom, eprom, prom, mrom, dekatron, 1952, selectron, 1951, mellon, 1946, williams, kilburn, vram, cam, content, addressable, qram, hbm, gddr, ddr, rdram, xdr, edo, qdrsram, lpddr, sgram, edram, scratchpad, kryder, moore, amdahl, dew, edge, fog, grid, switching, architectures, persistent, persistence, science, processing, rot, entropy, mapped, virtualization, logical, segmentation, partitioning, aggregation, mirroring, image, master, sector, rights, copy, protection, temporary, hex, backup, copying, deletion, knowledge, base, repository, refresh, replication, redundancy, deduplication, clustered, sharing, resource, directory, cluster, recovery, reconciliation, security, integrity, degradation, cleansing, corruption, compression, metadata, big, unstructured, structured, single, instance, area, direct, areal, density, continuous, availability, floating, gate, mos, map, types, diagram, free, encyclopedia, wayback, http, archive, 20221016140408, wiki, timestamps, capture, fail, success, 2023, nov, oct, feb, 2004, 2026, 363, captures,

Text of the page (random words):
memory hierarchy wikipedia 363 captures 23 feb 2004 21 sep 2026 sep oct nov 16 2021 2022 2023 success fail about this capture timestamps the wayback machine http web archive org web 20221016140408 https en wikipedia org wiki memory_hierarchy memory hierarchy from wikipedia the free encyclopedia jump to navigation jump to search computer architecture diagram of the computer memory hierarchy computer memory and data storage types general memory cell memory coherence cache coherence memory hierarchy memory access pattern memory map secondary storage mos memory floating gate continuous availability areal density computer storage block data storage object storage direct attached storage network attached storage storage area network block level storage single instance storage data structured data unstructured data big data metadata data compression data corruption data cleansing data degradation data integrity data security data validation data validation and reconciliation data recovery storage data cluster directory shared resource file sharing file system clustered file system distributed file system distributed file system for cloud distributed data store distributed database database data bank data storage data store data deduplication data structure data redundancy replication computing memory refresh storage record information repository knowledge base computer file object file file deletion file copying backup core dump hex dump data communication information transfer temporary file copy protection digital rights management volume computing boot sector master boot record volume boot record disk array disk image disk mirroring disk aggregation disk partitioning memory segmentation locality of reference logical disk storage virtualization virtual memory memory mapped file software entropy software rot in memory database in memory processing persistence computer science persistent data structure raid non raid drive architectures memory paging bank switching grid computing cloud computing cloud storage fog computing edge computing dew computing amdahl s law moore s law kryder s law volatile ram hardware cache cpu cache scratchpad memory dram edram sdram sgram lpddr qdrsram edo dram xdr dram rdram sdram ddr gddr hbm sram 1t sram reram qram content addressable memory cam vram dual ported ram video ram dual ported dram historical williams kilburn tube 1946 1947 delay line memory 1947 mellon optical memory 1951 selectron tube 1952 dekatron t ram 2009 z ram 2002 2010 non volatile rom mrom prom eprom eeprom rom cartridge solid state storage sss flash memory is used in solid state drive ssd solid state hybrid drive sshd usb flash drive ibm flashsystem flash core module memory card memory stick compactflash pc card multimediacard sd card sim card smartmedia universal flash storage sxs microp2 xqd card programmable metallization cell nvram memistor memristor pcm 3d xpoint mram electrochemical ram ecram nano ram cbram early stage nvram feram reram fefet memory analog recording phonograph cylinder phonograph record quadruplex videotape vision electronic recording apparatus magnetic recording magnetic storage magnetic tape magnetic tape data storage tape drive tape library digital data storage dds videotape videocassette cassette tape linear tape open betamax 8 mm video format dv minidv micromv u matic vhs s vhs vhs c d vhs hard disk drive optical 3d optical data storage optical disc laserdisc compact disc digital audio cdda cd cd video cd r cd rw video cd super video cd mini cd nintendo optical discs cd rom hyper cd rom dvd dvd r dvd video dvd card dvd ram minidvd hd dvd blu ray ultra hd blu ray holographic versatile disc worm in development cbram racetrack memory nram millipede memory ecram patterned media holographic data storage electronic quantum holography 5d optical data storage dna digital data storage universal memory time crystal quantum memory ultraram historical paper data storage 1725 punched card 1725 punched tape 1725 plugboard delay line memory drum memory 1932 magnetic core memory 1949 plated wire memory 1957 core rope memory 1960s thin film memory 1962 disk pack 1962 twistor memory 1968 bubble memory 1970 floppy disk 1971 v t e in computer architecture the memory hierarchy separates computer storage into a hierarchy based on response time since response time complexity and capacity are related the levels may also be distinguished by their performance and controlling technologies 1 memory hierarchy affects performance in computer architectural design algorithm predictions and lower level programming constructs involving locality of reference designing for high performance requires considering the restrictions of the memory hierarchy i e the size and capabilities of each component each of the various components can be viewed as part of a hierarchy of memories m 1 m 2 m n in which each member m i is typically smaller and faster than the next highest member m i 1 of the hierarchy to limit waiting by higher levels a lower level will respond by filling a buffer and then signaling for activating the transfer there are four major storage levels 1 internal processor registers and cache main the system ram and controller cards on line mass storage secondary storage off line bulk storage tertiary and off line storage this is a general memory hierarchy structuring many other structures are useful for example a paging algorithm may be considered as a level for virtual memory when designing a computer architecture and one can include a level of nearline storage between online and offline storage contents 1 properties of the technologies in the memory hierarchy 2 examples 3 see also 4 references properties of the technologies in the memory hierarchy edit adding complexity slows down the memory hierarchy 2 cmox memory technology stretches the flash space in the memory hierarchy 3 one of the main ways to increase system performance is minimising how far down the memory hierarchy one has to go to manipulate data 4 latency and bandwidth are two metrics associated with caches neither of them is uniform but is specific to a particular component of the memory hierarchy 5 predicting where in the memory hierarchy the data resides is difficult 5 the location in the memory hierarchy dictates the time required for the prefetch to occur 5 examples edit memory hierarchy of an amd bulldozer server the number of levels in the memory hierarchy and the performance at each level has increased over time the type of memory or storage components also change historically 6 for example the memory hierarchy of an intel haswell mobile 7 processor circa 2013 is processor registers the fastest possible access usually 1 cpu cycle a few thousand bytes in size cache level 0 l0 micro operations cache 6 144 bytes 6 kib citation needed original research 8 in size level 1 l1 instruction cache 128 kib citation needed original research in size level 1 l1 data cache 128 kib citation needed original research in size best access speed is around 700 gb s 9 level 2 l2 instruction and data shared 1 mib citation needed original research in size best access speed is around 200 gb s 9 level 3 l3 shared cache 6 mib citation needed original research in size best access speed is around 100 gb s 9 level 4 l4 shared cache 128 mib citation needed original research in size best access speed is around 40 gb s 9 main memory primary storage gib citation needed original research in size best access speed is around 10 gb s 9 in the case of a numa machine access times may not be uniform disk storage secondary storage terabytes in size as of 2017 best access speed is from a consumer solid state drive is about 2000 mb s 10 nearline storage tertiary storage up to exabytes in size as of 2013 best access speed is about 160 mb s 11 offline storage the lower levels of the hierarchy from disks downwards are also known as tiered storage the formal distinction between online nearline and offline storage is 12 online storage is immediately available for i o nearline storage is not immediately available but can be made online quickly without human intervention offline storage is not immediately available and requires some human intervention to bring online for example always on spinning disks are online while spinning disks that spin down such as massive array of idle disk maid are nearline removable media such as tape cartridges that can be automatically loaded as in a tape library are nearline while cartridges that must be manually loaded are offline most modern cpus are so fast that for most program workloads the bottleneck is the locality of reference of memory accesses and the efficiency of the caching and memory transfer between different levels of the hierarchy citation needed as a result the cpu spends much of its time idling waiting for memory i o to complete this is sometimes called the space cost as a larger memory object is more likely to overflow a small fast level and require use of a larger slower level the resulting load on memory use is known as pressure respectively register pressure cache pressure and main memory pressure terms for data being missing from a higher level and needing to be fetched from a lower level are respectively register spilling due to register pressure register to cache cache miss cache to main memory and hard page fault main memory to disk modern programming languages mainly assume two levels of memory main memory and disk storage though in assembly language and inline assemblers in languages such as c registers can be directly accessed taking optimal advantage of the memory hierarchy requires the cooperation of programmers hardware and compilers as well as underlying support from the operating system programmers are responsible for moving data between disk and memory through file i o hardware is responsible for moving data between memory and caches optimizing compilers are responsible for generating code that when executed will cause the hardware to use caches and registers efficiently many programmers assume one level of memory this works fine until the application hits a performance wall then the memory hierarchy will be assessed during code refactoring see also edit cache hierarchy use of spatial and temporal locality hierarchical memory buffer vs cache cache hierarchy in a modern processor memory wall computer memory hierarchical storage management cloud storage memory access pattern communication avoiding algorithm references edit a b toy wing zee benjamin 1986 computer hardware software architecture prentice hall p 30 isbn 0 13 163502 6 write combining memory hierarchy unitity semiconductor corporation archived from the original on 5 august 2009 retrieved 16 september 2009 pádraig brady multi core retrieved 16 september 2009 a b c van der pas ruud 2002 memory hierarchy in cache based systems pdf santa clara california sun microsystems 26 817 0742 10 cite journal cite journal requires journal help memory storage timeline of computer history computer history museum www computerhistory org crothers brooke dissecting intel s top graphics in apple s 15 inch macbook pro cnet news cnet com retrieved 2014 07 31 intel s haswell architecture analyzed building a new pc and a new intel anandtech retrieved 2014 07 31 a b c d e sisoftware zone sisoftware co uk archived from the original on 2014 09 13 retrieved 2014 07 31 samsung 960 pro m 2 nvme ssd review storagereview com retrieved 2017 04 13 ultrium lto technology ultrium generationslto lto org archived from the original on 2011 07 27 retrieved 2014 07 31 pearson tony 2010 correct use of the term nearline ibm developerworks inside system storage archived from the original on 2018 11 27 retrieved 2015 08 16 retrieved from https en wikipedia org w index php title memory_hierarchy oldid 1086513241 categories computer architecture computer data storage hierarchy hidden categories cs1 errors missing periodical articles with short description short description is different from wikidata all articles with unsourced statements articles with unsourced statements from may 2021 all articles that may contain original research articles that may contain original research from may 2021 articles with unsourced statements from september 2009 navigation menu personal tools not logged in talk contributions create account log in namespaces article talk english views read edit view history more search navigation main page contents current events random article about wikipedia contact us donate contribute help learn to edit community portal recent changes upload file tools what links here related changes upload file special pages permanent link page information cite this page wikidata item print export download as pdf printable version in other projects wikimedia commons languages العربية català deutsch español فارسی français 한국어 bahasa indonesia עברית қазақша nederlands português русский српски srpski türkçe українська 中文 edit links this page was last edited on 6 may 2022 at 16 05 utc text is available under the creative commons attribution sharealike license 3 0 additional terms may apply by using this site you agree to the terms of use and privacy policy wikipedia is a registered trademark of the wikimedia foundation inc a non profit organization privacy policy about wikipedia disclaimers contact wikipedia mobile view developers statistics cookie statement