On Wed, Mar 2, 2011 at 8:17 AM, Jason Rutherglen <jason.rutherg...@gmail.com> wrote: > Todd, > > Thanks for the reply. I looked at HDFS-941 which seems to remove the > redundant creation of BlockReaders. That and HDFS-347 will solve some > of the issues, however I think there's also the sendmsg() of the file > descriptor that also needs to be implemented?
Yes, see HADOOP-6311. I have an up-to-date patch on this but have not yet gotten to posting it since we need 347 to be redone on trunk as well. -Todd > On Tue, Mar 1, 2011 at 5:58 PM, Todd Lipcon <t...@cloudera.com> wrote: >> Hi Jason, >> >> Yes, this method is currently very inefficient.. HDFS-941 will >> hopefully improve this situation, but currently there's no >> particularly efficient way to do multithreaded random access. >> >> -Todd >> >> On Tue, Mar 1, 2011 at 4:24 PM, Jason Rutherglen >> <jason.rutherg...@gmail.com> wrote: >>> It's unsynchronized however it's creating a new BlockReader on each >>> call, that seems like a problem? >>> >> >> >> >> -- >> Todd Lipcon >> Software Engineer, Cloudera >> > -- Todd Lipcon Software Engineer, Cloudera
