4 ms·
Last I looked (~4.4) linux AIO implied DIO. Conflating aio and dio is the problem, not a feature. On FreeBSD AIO works with the page cache for read and write, r
by donavanm 9y ago
Last I looked (~4.4) linux AIO implied DIO. Conflating aio and dio is the problem, not a feature. On FreeBSD AIO works with the page cache for read and write, read ahead works, sendfile works, io & cache & readahead & size hints all work. Linux has half of those, and DIO none. As i recall.
- tatersolid 9y agoBingo. Async disk IO on Linux has to be unbuffered and block aligned. Making it useful only for databases that manage their own caching, and useless for file systems. A video CDN needs lots of concurrent access to a file system.