Hi Jutta, On Wed, Jan 9, 2013 at 7:11 AM, Lachfeld, Jutta <jutta.lachfeld@xxxxxxxxxxxxxx> wrote: > > the current content of the web page http://ceph.com/docs/master/cephfs/hadoop shows a configuration parameter ceph.object.size. > Is it the CEPH equivalent to the "HDFS block size" parameter which I have been looking for? Yes. By specifying ceph.object.size, the Hadoop will use a default Ceph file layout with stripe unit = object size, and stripe count = 1. This is effectively the same meaning as dfs.block.size for HDFS. > Does the parameter ceph.object.size apply to version 0.56.1? The Ceph/Hadoop file system plugin is being developed here: git://github.com/ceph/hadoop-common cephfs/branch-1.0 There is an old version of the Hadoop plugin in the Ceph tree which will be removed shortly. Regarding the versions, development is taking place in cephfs/branch-1.0 and in ceph.git master. We don't yet have a system in place for dealing with compatibility across versions because the code is in heavy development. If you are running 0.56.1 then a recent version of cephfs/branch-1.0 should work with that, but may not long, as development continues. > I would be interested in setting this parameter to values higher than 64MB, e.g. 256MB or 512MB similar to the values I have used for HDFS for increasing the performance of the TeraSort benchmark. Would these values be allowed and would they at all make sense for the mechanisms used in CEPH? I can't think of any reason why a large size would cause concern, but maybe someone else can chime in? - Noah -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
