Hi all, One of the grey areas (in terms of documentation) is how to turn off readdirplus (aka readdirp) in the entire stack of glusterfs. The confusion is because, there are couple of xlators which by default convert a readdir into readdirp. All of the following steps need to be done to turn off readdirp entirely.
1. mount glusterfs with option --use-readdirp=no (disables readdirp between fuse kernel module and glusterfs) [root@unused glusterfs]# mount -t glusterfs booradley:/testvol -o use-readdirp=no /mnt/glusterfs [root@unused glusterfs]# ps ax | grep -i mnt 26096 ? Ssl 0:00 /usr/local/sbin/glusterfs --use-readdirp=no --volfile-server=booradley --volfile-id=/testvol /mnt/glusterfs 2. set performance.force-readdirp to false (prevents md-cache from converting readdir calls to readdirp) [root@unused glusterfs]# gluster volume set testvol performance.force-readdirp off volume set: success 3. set dht.force-readdirp to false (prevents dht from converting readdir into readdirp [root@unused glusterfs]# gluster volume set testvol dht.force-readdirp off volume set: success [root@unused glusterfs]# gluster volume info testvol Volume Name: testvol Type: Distribute Volume ID: 007edfec-0e54-4d80-bef4-9aec5bcc1108 Status: Started Snapshot Count: 0 Number of Bricks: 1 Transport-type: tcp Bricks: Brick1: booradley:/home/export/testvol Options Reconfigured: dht.force-readdirp: off performance.force-readdirp: off transport.address-family: inet nfs.disable: on Note that if readdir-ahead is turned on, by default it does prefetch directory entries to fill its cache using readdirp. However, it doesn't implement readdirp fop. Hence those prefetched entries are never consumed in the above configuration. If option performance.readdir-ahead is set to off, we wouldn't not witness a readdirp fop in the entire glusterfs stack (from fuse till bricks). regards, Raghavendra _______________________________________________ Gluster-devel mailing list Gluster-devel@gluster.org http://lists.gluster.org/mailman/listinfo/gluster-devel
