forked from Minki/linux
ae82ddbfeb
This works in conjunction with the new PI controller. Currently, in real-world workloads, the rate controller attempts to write back 1 sector per second. In practice, these minimum-rate writebacks are between 4k and 60k in test scenarios, since bcache aggregates and attempts to do contiguous writes and because filesystems on top of bcachefs typically write 4k or more. Previously, bcache used to guarantee to write at least once per second. This means that the actual writeback rate would exceed the configured amount by a factor of 8-120 or more. This patch adjusts to be willing to sleep up to 2.5 seconds, and to target writing 4k/second. On the smallest writes, it will sleep 1 second like before, but many times it will sleep longer and load the backing device less. This keeps the loading on the cache and backing device related to writeback more consistent when writing back at low rates. Signed-off-by: Michael Lyle <mlyle@lyle.org> Reviewed-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk> |
||
|---|---|---|
| .. | ||
| alloc.c | ||
| bcache.h | ||
| bset.c | ||
| bset.h | ||
| btree.c | ||
| btree.h | ||
| closure.c | ||
| closure.h | ||
| debug.c | ||
| debug.h | ||
| extents.c | ||
| extents.h | ||
| io.c | ||
| journal.c | ||
| journal.h | ||
| Kconfig | ||
| Makefile | ||
| movinggc.c | ||
| request.c | ||
| request.h | ||
| stats.c | ||
| stats.h | ||
| super.c | ||
| sysfs.c | ||
| sysfs.h | ||
| trace.c | ||
| util.c | ||
| util.h | ||
| writeback.c | ||
| writeback.h | ||