Wolfgang Alper: > If the above seems to be correct, my question would be if there is an option > to cache branch information or something similar to avoid re-reading branches > (readdir), since the entire mountPoint can be considered RO (even the first > branch if needed) and no udba is in effect.
The options to avoid re-issuing readdir to branches and cache the results are rdcache= and others which you already specified. So we should confirm first whether the options work expectedly or not. I cannot test it by myself because your kernel/aufs version is unknown to me. Remember I am not an ubuntu user and I don't know why they chose very old 20091207 version for their release in Apr 2010. Looking at http://kernel.ubuntu.com/git?p=ubuntu/ubuntu-lucid.git;a=summary, there are lots of updates and I am afraid your version is not latest. It means if I send you a small debug print patch to show when and why aufs issues readdir for branch, it may not be applied correctly due to your version is old and ubuntu people may modify the source files which I cannot confirm. The easy way to find which operation is issued to the ftp server is watching on the ftp server. But you wrote that you don't know which operation is issued. So here is my suggestion. Test aufs readdir caching by using branches other than fuse. For example, - create a dir on your local ext2. - create many empty files under the dir. - mount aufs as specifying the dir is a branch. - run ls several times. - usually "mount -o remount /your/aufs" discards caches. also "rdcache=0" option does too. With this environment, you will see whether the readdir cache in aufs works expectedly or not. J. R. Okajima ------------------------------------------------------------------------------ This SF.net email is sponsored by Sprint What will you do first with EVO, the first 4G phone? Visit sprint.com/first -- http://p.sf.net/sfu/sprint-com-first
