fuse: optimize writepages search
Re-work fi->writepages, replacing list with rb-tree. This improves
performance because kernel fuse iterates through fi->writepages for each
writeback page and typical number of entries is about 800 (for 100MB of
fuse writeback).
Before patch:
10240+0 records in
10240+0 records out
10737418240 bytes (11 GB) copied, 41.3473 s, 260 MB/s
2 1 0 57445400 40416 6323676 0 0 33 374743 8633 19210 1 8 88 3 0
29.86% [kernel] [k] _raw_spin_lock
26.62% [fuse] [k] fuse_page_is_writeback
After patch:
10240+0 records in
10240+0 records out
10737418240 bytes (11 GB) copied, 21.4954 s, 500 MB/s
2 9 0 53676040 31744 10265984 0 0 64 854790 10956 48387 1 6 88 6 0
23.55% [kernel] [k] copy_user_enhanced_fast_string
9.87% [kernel] [k] __memcpy
3.10% [kernel] [k] _raw_spin_lock
Signed-off-by: Maxim Patlasov <mpatlasov@virtuozzo.com>
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index d7cde216..740a8a7 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -111,7 +111,7 @@ struct fuse_inode {
wait_queue_head_t page_waitq;
/* List of writepage requestst (pending or sent) */
- struct list_head writepages;
+ struct rb_root writepages;
};
/* readdir cache (directory only) */
