[$] A discussion on readahead

Post Syndicated from original https://lwn.net/Articles/897786/

Readahead is an I/O
optimization that causes the system to read more data than
has been requested by an application—in the belief that the extra data will
be requested soon thereafter. At the
2022 Linux Storage,
Filesystem, Memory-management and BPF Summit
(LSFMM), Matthew Wilcox
led a session to discuss readahead, especially as it relates to network
filesystems, with assistance from Steve French and
David Howells. The latency of the underlying storage needs to factor into
the calculation of how much data to read in advance, but it is not entirely
clear how to do so.