Phillip Lougher wrote: > If I read the patches correctly, when a file page is written to, only > that page gets copied into the page cache and locked, the other pages > continue to be read off disk from cramfs? With Unionfs a page write > causes the entire file to be copied up to the r/w tmpfs and locked into > the page cache causing unnecessary RAM overhead. Ok, so why not fix that in unionfs? An option so that holes in the overlay file let through data from the underlying file sounds like it would be generally useful, and quite easy to implement. If not unionfs, a "union-tmpfs" combination would be good. Many filesystems aren't well suited to being the overlay filesystem - adding to the implementation's complexity - but a modified tmpfs could be very well suited. -- Jamie -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
