Many Linux distributions use readahead on a list of commonly used files to speed up booting. In such a setup, if the kernel is booted with the profileboot parameter, it will record all file accesses during bootup and write a new list of files to be read during later boot sequences. This will make additional installed services start faster, because they are not included in the default readahead list.[3]
In Linux distributions that use systemd, readahead binary (as part of the boot sequence) was replaced by systemd-readahead.[4][5] However, support for readahead was removed from systemd in its version 217, being described as unmaintained and unable to provide expected performance benefits.[6]
Certain experimental page-level prefetching systems have been developed to further improve performance.[7]
In filesystemEdit
Bcache support readahead of files and metadata.[8]
ZFS supports readahead of files and metadata, when using ARC.[9]
^. freedesktop.org. 2014-03-26. Archived from the original on 2014-04-09. Retrieved 2014-04-09.
^"systemd/systemd – System and Session Manager: Changes with 217". cgit.freedesktop.org. Retrieved 2018-02-09.
^Krzysztof Lichota (2008). (PDF). code.google.com. Archived from the original (PDF) on 2009-12-11. Retrieved 2014-07-28.
^"bcache.txt\Documentation - linux-bcache.git - Unnamed repository; edit this file 'description' to name the repository". evilpiepirate.org. Retrieved 1 May 2020.
^"Part 10 - Monitoring and Tuning ZFS Performance| Oracle Community". community.oracle.com. Retrieved 1 May 2020.
This Linux-related article is a stub. You can help Wikipedia by expanding it.
readahead, readahead, system, call, linux, kernel, that, loads, file, contents, into, page, cache, this, prefetches, file, that, when, subsequently, accessed, contents, read, from, main, memory, rather, than, from, hard, disk, drive, resulting, much, lower, fi. Readahead is a system call of the Linux kernel that loads a file s contents into the page cache This prefetches the file so that when it is subsequently accessed its contents are read from the main memory RAM rather than from a hard disk drive HDD resulting in much lower file access latencies 1 2 Many Linux distributions use readahead on a list of commonly used files to speed up booting In such a setup if the kernel is booted with the profile boot parameter it will record all file accesses during bootup and write a new list of files to be read during later boot sequences This will make additional installed services start faster because they are not included in the default readahead list 3 In Linux distributions that use systemd readahead binary as part of the boot sequence was replaced by systemd readahead 4 5 However support for readahead was removed from systemd in its version 217 being described as unmaintained and unable to provide expected performance benefits 6 Certain experimental page level prefetching systems have been developed to further improve performance 7 In filesystem EditBcache support readahead of files and metadata 8 ZFS supports readahead of files and metadata when using ARC 9 References Edit Jonathan Corbet 2005 10 12 Adaptive file readahead LWN net Retrieved 2014 08 20 readahead 2 Linux manual page man7 org Retrieved 2014 04 09 Michael Opdenacker 2007 06 15 Readahead time travel techniques for desktop and embedded systems PDF free electrons com pp 5 6 Retrieved 2014 05 01 Readahead fedorahosted org Retrieved 2014 04 09 systemd readahead replay service freedesktop org 2014 03 26 Archived from the original on 2014 04 09 Retrieved 2014 04 09 systemd systemd System and Session Manager Changes with 217 cgit freedesktop org Retrieved 2018 02 09 Krzysztof Lichota 2008 Linux solution for prefetching necessary data during application and system startup PDF code google com Archived from the original PDF on 2009 12 11 Retrieved 2014 07 28 bcache txt Documentation linux bcache git Unnamed repository edit this file description to name the repository evilpiepirate org Retrieved 1 May 2020 Part 10 Monitoring and Tuning ZFS Performance Oracle Community community oracle com Retrieved 1 May 2020 This Linux related article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Readahead amp oldid 1121395460, wikipedia, wiki, book, books, library,
