Ping to see if this patch can get picked up. On Fri, Jan 3, 2014 at 10:11 AM, Seth Jennings <sjennings@xxxxxxxxxxxxxx> wrote: > On Thu, Dec 19, 2013 at 08:23:27AM -0500, Dan Streetman wrote: >> Currently, zswap is writeback cache; stored pages are not sent >> to swap disk, and when zswap wants to evict old pages it must >> first write them back to swap cache/disk manually. This avoids >> swap out disk I/O up front, but only moves that disk I/O to >> the writeback case (for pages that are evicted), and adds the >> overhead of having to uncompress the evicted pages and the >> need for an additional free page (to store the uncompressed page). >> >> This optionally changes zswap to writethrough cache by enabling >> frontswap_writethrough() before registering, so that any >> successful page store will also be written to swap disk. The >> default remains writeback. To enable writethrough, the param >> zswap.writethrough=1 must be used at boot. >> >> Whether writeback or writethrough will provide better performance >> depends on many factors including disk I/O speed/throughput, >> CPU speed(s), system load, etc. In most cases it is likely >> that writeback has better performance than writethrough before >> zswap is full, but after zswap fills up writethrough has >> better performance than writeback. >> >> Signed-off-by: Dan Streetman <ddstreet@xxxxxxxx> > > Hey Dan, sorry for the delay on this. Vacation and busyness. > > This looks like a good option for those that don't mind having > the write overhead to ensure that things don't really bog down > if the compress pool overflows, while maintaining the read fault > speedup by decompressing from the pool. > > Acked-by: Seth Jennings <sjennings@xxxxxxxxxxxxxx> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>