mirror of
https://github.com/torvalds/linux
synced 2024-10-04 10:26:40 +00:00
dd2a434373
At the moment, line metadata is persisted on a separate work queue, that is kicked each time that a line is closed. The assumption when designing this was that freeing the write thread from creating a new write request was better than the potential impact of writes colliding on the media (user I/O and metadata I/O). Experimentation has proven that this assumption is wrong; collision can cause up to 25% of bandwidth and introduce long tail latencies on the write thread, which potentially cause user write threads to spend more time spinning to get a free entry on the write buffer. This patch moves the metadata logic to the write thread. When a line is closed, remaining metadata is written in memory and is placed on a metadata queue. The write thread then takes the metadata corresponding to the previous line, creates the write request and schedules it to minimize collisions on the media. Using this approach, we see that we can saturate the media's bandwidth, which helps reducing both write latencies and the spinning time for user writer threads. Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <matias@cnexlabs.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> |
||
|---|---|---|
| .. | ||
| core.c | ||
| Kconfig | ||
| Makefile | ||
| pblk-cache.c | ||
| pblk-core.c | ||
| pblk-gc.c | ||
| pblk-init.c | ||
| pblk-map.c | ||
| pblk-rb.c | ||
| pblk-read.c | ||
| pblk-recovery.c | ||
| pblk-rl.c | ||
| pblk-sysfs.c | ||
| pblk-write.c | ||
| pblk.h | ||
| rrpc.c | ||
| rrpc.h | ||