| abstract | - readahead is a system call of the Linux kernel that loads a file's contents into the page cache, providing that way a file prefetching technology. When a file 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 due to much higher bandwidth of the main memory. 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. In Linux distributions that use systemd, readahead binary (as part of the boot sequence) is replaced by systemd-readahead.. In debian-beisen plätforms laik Ubuntu, nigè softwär wa folowen jenereiçion konsisten:
* readahead: obsoleten sins Ubuntu 9.10
* sreadahead: ripleisiŋ readahead. Osou obsoleten bai ureadahead.
* ureadahead: Doüčiš: über-readahead dè suokxie, neim wa orijineiten from Doüčiš. sreadahead dè rīpleismènt in Ubuntu. Jigùm-dè vörçion wa 0.100.0-17. Certain experimental page-level prefetching systems have been developed to further improve performance.
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