diff options
| author | David Howells <[email protected]> | 2024-07-01 23:40:22 +0000 |
|---|---|---|
| committer | Christian Brauner <[email protected]> | 2024-09-12 10:20:41 +0000 |
| commit | ee4cdf7ba857a894ad1650d6ab77669cbbfa329e (patch) | |
| tree | 8258e3b756adf109085d66a8b63cd08db03abad0 /fs/netfs/stats.c | |
| parent | afs: Make read subreqs async (diff) | |
| download | kernel-ee4cdf7ba857a894ad1650d6ab77669cbbfa329e.tar.gz kernel-ee4cdf7ba857a894ad1650d6ab77669cbbfa329e.zip | |
netfs: Speed up buffered reading
Improve the efficiency of buffered reads in a number of ways:
(1) Overhaul the algorithm in general so that it's a lot more compact and
split the read submission code between buffered and unbuffered
versions. The unbuffered version can be vastly simplified.
(2) Read-result collection is handed off to a work queue rather than being
done in the I/O thread. Multiple subrequests can be processes
simultaneously.
(3) When a subrequest is collected, any folios it fully spans are
collected and "spare" data on either side is donated to either the
previous or the next subrequest in the sequence.
Notes:
(*) Readahead expansion is massively slows down fio, presumably because it
causes a load of extra allocations, both folio and xarray, up front
before RPC requests can be transmitted.
(*) RDMA with cifs does appear to work, both with SIW and RXE.
(*) PG_private_2-based reading and copy-to-cache is split out into its own
file and altered to use folio_queue. Note that the copy to the cache
now creates a new write transaction against the cache and adds the
folios to be copied into it. This allows it to use part of the
writeback I/O code.
Signed-off-by: David Howells <[email protected]>
cc: Jeff Layton <[email protected]>
cc: [email protected]
cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]/ # v2
Signed-off-by: Christian Brauner <[email protected]>
Diffstat (limited to 'fs/netfs/stats.c')
| -rw-r--r-- | fs/netfs/stats.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/fs/netfs/stats.c b/fs/netfs/stats.c index 5065289f5555..8e63516b40f6 100644 --- a/fs/netfs/stats.c +++ b/fs/netfs/stats.c @@ -32,6 +32,7 @@ atomic_t netfs_n_wh_buffered_write; atomic_t netfs_n_wh_writethrough; atomic_t netfs_n_wh_dio_write; atomic_t netfs_n_wh_writepages; +atomic_t netfs_n_wh_copy_to_cache; atomic_t netfs_n_wh_wstream_conflict; atomic_t netfs_n_wh_upload; atomic_t netfs_n_wh_upload_done; @@ -51,11 +52,12 @@ int netfs_stats_show(struct seq_file *m, void *v) atomic_read(&netfs_n_rh_read_folio), atomic_read(&netfs_n_rh_write_begin), atomic_read(&netfs_n_rh_write_zskip)); - seq_printf(m, "Writes : BW=%u WT=%u DW=%u WP=%u\n", + seq_printf(m, "Writes : BW=%u WT=%u DW=%u WP=%u 2C=%u\n", atomic_read(&netfs_n_wh_buffered_write), atomic_read(&netfs_n_wh_writethrough), atomic_read(&netfs_n_wh_dio_write), - atomic_read(&netfs_n_wh_writepages)); + atomic_read(&netfs_n_wh_writepages), + atomic_read(&netfs_n_wh_copy_to_cache)); seq_printf(m, "ZeroOps: ZR=%u sh=%u sk=%u\n", atomic_read(&netfs_n_rh_zero), atomic_read(&netfs_n_rh_short_read), |