It has come a long way since 0.18 and facebook keeps our (0.17) dfs mounted via 
fuse and uses that for some operations.

There have recently been some problems with fuse-dfs when used in a 
multithreaded environment, but those have been fixed in 0.18.2 and 0.19. (do 
not use 0.18 or 0.18.1)

The current (known) issues are:
  1. Wrong semantics when copying over an existing file - namely it does a 
delete and then re-creates the file, so ownership/permissions may end up wrong. 
There is a patch for this.
  2. When directories have 10s of thousands of files, performance can be very 
poor.
  3. Posix truncate is supported only for truncating it to 0 size since hdfs 
doesn't support truncate.
  4. Appends are not supported - this is a libhdfs problem and there is a patch 
for it.

It is still a pre-1.0 product for sure, but it has been pretty stable for us.


-- pete


On 10/31/08 9:08 AM, "Robert Krüger" <[EMAIL PROTECTED]> wrote:



Hi,

could anyone tell me what the current Status of FUSE support for HDFS
is? Is this something that can be expected to be usable in a few
weeks/months in a production environment? We have been really
happy/successful with HDFS in our production system. However, some
software we use in our application simply requires an OS-Level file
system which currently requires us to do a lot of copying between HDFS
and a regular file system for processes which require that software and
FUSE support would really eliminate that one disadvantage we have with
HDFS. We wouldn't even require the performance of that to be outstanding
because just by eliminatimng the copy step, we would greatly increase
the thruput of those processes.

Thanks for sharing any thoughts on this.

Regards,

Robert


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