Hello Raghavendra, Raghavendra G wrote: > Hi Deian, > > On Fri, Oct 10, 2008 at 8:51 PM, Deian Chepishev > <dchepishev at nexbrod.com <mailto:dchepishev at nexbrod.com>> wrote: > > Hi guys, > > I have a few questions about UNIFY and volume creation. > > You will find my config files at the end of this post. I will post my > questions before the config. > > 1. I want to use writebehind and readahead translators, because I > think > it speeds the transfer. Can you please take a look i let me know if it > is correctly written. > I basically do this: > create one volume from the exported bricks lets say "unify" > create another volume named "writebehind" with subvolumes unify > then create another volume named "readahead" with subvolumes > writebehind > then mount the volume named writebehind. > > > If you are using --volume-name option to glusterfs to attach to > writebehind, then you are bypassing readahead and hence will not get > readahead functionality. If you want to have both read-ahead and > write-behind functionalities, do not specify --volume-name option (or > give readahead as the argument to the option, if at all you want to > use it). ===> I am even more confused by your answer :). I want to have single volume for which I want load both translators readahead and writebehind. That is why I thought that this is accomplished with the above mentioned definition scheme. Looks like I am wrong. What is the correct way to define the volume in order to have both translators loaded for it ? > > > I have the following server and client files: > > > volume brick > type storage/posix > option directory /storage/gluster-export/data/ > end-volume > > volume brick-ns > type storage/posix > option directory /storage/gluster-export/ns > end-volume > > ### Add network serving capability to above brick. > > volume server > type protocol/server > option transport-type tcp/server > subvolumes brick brick-ns > option auth.ip.brick.allow 10.1.124. <http://10.1.124.>* > option auth.ip.brick-ns.allow 10.1.124. <http://10.1.124.>* > end-volume > > ========================= > > Client: > > volume brick1-stor01 > type protocol/client > option transport-type tcp/client > option remote-host 10.1.124.200 <http://10.1.124.200> > option remote-subvolume brick > end-volume > > volume brick1-stor02 > type protocol/client > option transport-type tcp/client > option remote-host 10.1.124.201 <http://10.1.124.201> > option remote-subvolume brick > end-volume > > volume brick-ns1 > type protocol/client > option transport-type tcp/client > option remote-host 10.1.124.200 <http://10.1.124.200> > option remote-subvolume brick-ns > end-volume > > > volume brick-ns2 > type protocol/client > option transport-type tcp/client > option remote-host 10.1.124.201 <http://10.1.124.201> > option remote-subvolume brick-ns # Note the different remote > volume name. > end-volume > > volume afr-ns > type cluster/afr > subvolumes brick-ns1 brick-ns2 > end-volume > > volume unify > type cluster/unify > option namespace afr-ns > option scheduler rr > option scheduler alu # use the ALU scheduler > option alu.limits.min-free-disk 5% # Don't create files one a > volume with less than 5% free diskspace > option alu.limits.max-open-files 10000 # Don't create files on a > volume with more than 10000 files open > option alu.order > disk-usage:read-usage:write-usage:open-files-usage:disk-speed-usage > option alu.disk-usage.entry-threshold 100GB # Kick in if the > discrepancy in disk-usage between volumes is more than 2GB > option alu.disk-usage.exit-threshold 50MB # Don't stop writing to > the least-used volume until the discrepancy is 1988MB > option alu.open-files-usage.entry-threshold 1024 # Kick in if the > discrepancy in open files is 1024 > option alu.open-files-usage.exit-threshold 32 # Don't stop > until 992 > files have been written the least-used volume > option alu.stat-refresh.interval 10sec # Refresh the statistics > used > for decision-making every 10 seconds > subvolumes brick1-stor01 brick1-stor02 > end-volume > > volume writebehind > type performance/write-behind > option aggregate-size 512kb # default is 0bytes > option flush-behind on # default is 'off' > subvolumes unify > end-volume > > volume readahead > type performance/read-ahead > option page-size 512kB > option page-count 4 > option force-atime-update off > subvolumes writebehind > end-volume > Thank you. Regards, Deian
