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 filesystem
Bcache supports readahead of files and metadata.[8]
ZFS supports readahead of files and metadata, when using ARC.[9]
