Interested in algorithm (s). Who cites the term "caching" - read it as "disk buffering". I would like to hear in detail about Read-ahead/read-behind

We kindly request - do not respond conceptually! I read a lot of review articles. And the second request - do not discuss here other types of caching, such as hardware RAID controllers. And even more so the software.

Question

Interested in logic embedded in the controller and the sequence of actions that the equipment produces in order to speed up the read operation.

Closed due to the fact that the issue is too general for the participants D-side , HamSter , aleksandr barakin , Kromster , Bald 23 Dec '16 at 5:44 .

Please correct the question so that it describes the specific problem with sufficient detail to determine the appropriate answer. Do not ask a few questions at once. See “How to ask a good question?” For clarification. If the question can be reformulated according to the rules set out in the certificate , edit it .

  • one
    In fact, if you follow one of Knut's quotations, “People who are really interested in computers should know at least some ideas about what the“ hardware ”they use. Otherwise, the programs they write will be quite incomprehensible . " This is a very valuable question. - avp
  • 2
    @avp, this is a very valuable question - this question, in my opinion, is of no value to the knowledge base. the answer to it could be valuable, but those who can give a reasoned answer, alas, “do not go on every Internet site”. - aleksandr barakin
  • @alexanderbarakin, the answers without a question (and even on such an unexpected topic) will not appear. So I would love to read how the HP firmware differs from the Hitachi and Seagate firmware for basically the same SAS HDD, designed, for example, for HP XP (or no different ...). - avp
  • @avp, do not appear - appear regularly. called "articles" and "books." published on thematic resources. Often - paper. - aleksandr barakin
  • A little about the disk "from the inside" , note that the number of sectors on the tracks is different. As for caching, as I understand it, disk drives use the term disk buffer of a typical size of 8-256 Mbit (according to my estimates, quite a bit) in which they save sectors (512 bytes (4 kilobits) each) that pass under the head during the search the requested sector. - avp

0