sorry, in my test they dont get distributed equally. the new volume gehts more files (all files with the same size).
How exactly the distribution algorithm works would be interesting?! :-)

Moritz

Am 22.07.2009 um 14:25 schrieb Moritz Krinke:

Barry,

i just did a test about that.
if you add another subvolume to the DHT volume and add new files into an existing directory they will be distributed over all DHT- subvolumes.

I assume that the distribution on old subvolumes will stop when the free-space threshold is reached, but i did not test that.

Moritz


Am 21.07.2009 um 18:57 schrieb Barry Jaspan:

I have a question about this paragraph from the "Understanding DHT Translator":

"Currently hash works based on directory level distribution. i.e, a given file's parent directory will have information of how the hash numbers are mapped to subvolumes. So, adding new node doesn't disturb any current setup as the files/dirs present already have its information preserved. Whatever new directory gets created, will start considering new volume for scheduling files."

The last sentence suggests that if I have a single directory on a DHT volume and it is getting full, adding additional subvolumes to the DHT volume will not help because all the files in a directory will only ever live in subvolumes that existed at the time the directory is created. Is that true?

Also, it sounds like an entry mapping each filename (hash number) to a subvolume is stored in the extended attributes of the parent directory for that file. What is the practical limit for the number of files that can be stored in a single directory under this system? It seems like eventually doing a lookup in the directory's attributes would itself become a very expensive operation.

Thanks,
Barry

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