Christian Schoenebeck wrote on Sun, Apr 02, 2023 at 04:07:51PM +0200: > > So, mapping of existing (deprecated) legacy modes: > > - none (obvious) write_policy=writethrough > > - *readahead -> cache=file cache_validate_open write_policy=writethrough > > - mmap -> cache=file cache_validate=open write_policy=writeback > > Mmm, why is that "file"? To me "file" sounds like any access to files is > cached, whereas cache=mmap just uses the cache if mmap() was called, not for > any other file access. The semantics are slightly different but I don't think anyone would mind; mmap was introduced as a way of having minimal caching but file caching + /sys/class/bdi/9p*/max_bytes to 0 should be almost identical once we've made sure our cache code sends bigger than 4k writes at a time (I *think* that's still a problem and there was netfs work in the ways, but you'd have noticed?) -- Dominique
