From: Miklos Szeredi Date: Wed, 1 Feb 2006 11:04:40 +0000 (-0800) Subject: [PATCH] fuse: fix async read for legacy filesystems X-Git-Tag: v2.6.16-rc2~162 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9cd684551124e71630ab96d238747051463f5b56;p=pandora-kernel.git [PATCH] fuse: fix async read for legacy filesystems While asynchronous reads mean a performance improvement in most cases, if the filesystem assumed that reads are synchronous, then async reads may degrade performance (filesystem may receive reads out of order, which can confuse it's own readahead logic). With sshfs a 1.5 to 4 times slowdown can be measured. There's also a need for userspace filesystems to know whether asynchronous reads are supported by the kernel or not. To achive these, negotiate in the INIT request whether async reads will be used and the maximum readahead value. Update interface version to 7.6 If userspace uses a version earlier than 7.6, then disable async reads, and set maximum readahead value to the maximum read size, as done in previous versions. Signed-off-by: Miklos Szeredi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Reading git-diff-tree failed