Just to clarify: > On Windows especially context switching during I/O like that has a > high penalty.
should read > Context switching during I/O like that has a penalty. I know we are talking about Mono on Linux here. After all the subject is FUSE. I forgot to fix that statement before hitting 'send'. :-) ----- Original Message ---- > From: Andrew Purtell <apurt...@apache.org> > To: hbase-user@hadoop.apache.org > Sent: Sun, January 10, 2010 11:30:42 AM > Subject: Re: Basic question about using C# with Hadoop filesystems > > Bear in mind that hdfs-fuse has something like a 30% performance impact > when compared with direct access via the Java API. The data path is > something like: > > your app -> kernel -> libfuse -> JVM -> kernel -> HDFS > > HDFS -> kernel-> JVM -> libfuse -> kernel -> your app > > On Windows especially context switching during I/O like that has a > high penalty. Maybe it would be better to bind the C libhdfs API > directly via a C# wrapper (see http://wiki.apache.org/hadoop/LibHDFS). > But, at that point, you have pulled the Java Virtual Machine into the > address space of your process and are bridging between Java land and > C# land over the JNI and the C# equivalent. So, at this point, why not > just use Java instead of C#? Or, just use C and limit the damage to > only one native-to-managed interface instead of two? > > The situation will change somewhat when/if all HDFS RPC is moved to > some RPC and serialization scheme which is truly language independent, > i.e. Avro. I have no idea when or if that will happen. Even if that > happens, as Ryan said before, the HDFS client is fat. Just talking > the RPC gets you maybe 25% of the way toward a functional HDFS > client. > > The bottom line is the Hadoop software ecosystem has a strong Java > affinity. > > - Andy > > > > ----- Original Message ---- > > From: Jean-Daniel Cryans > > To: hbase-user@hadoop.apache.org > > Sent: Sun, January 10, 2010 8:57:32 AM > > Subject: Re: Basic question about using C# with Hadoop filesystems > > > > http://code.google.com/p/hdfs-fuse/ > > > > On Sun, Jan 10, 2010 at 7:36 AM, Aram Mkhitaryan > > wrote: > > > ah, sorry, forgot to mention, it's in hdfs-user mailing list > > > hdfs-u...@hadoop.apache.org
