I reckon that to quickly copy one glusterfs volume to another, I will need a multi-threaded 'cp'. That is, something which will take the list of files from readdir() and copy batches of N of them in parallel. This is so I can keep all the component spindles busy. Question 1: does such a thing existing already in the open source world? Question 2: for a DHT volume, does readdir() return the files in a round-robin fashion, i.e. one from brick 1, one from brick 2, one from brick 3 etc? Or does it return all the results from one brick, followed by all the results from the second brick, and so on? Or something indeterminate? Alternatively: is it possible to determine for each file which brick it resides on? (I don't think it's in an extended attribute; I tried 'getfattr -d' on a file, both on the GlusterFS mount and on the underlying brick, and couldn't see anything) Thanks, Brian. P.S. I did look in the source, and I couldn't figure out how dht_do_readdir works. But it does have a slightly disconcerting comment: /* TODO: do proper readdir */
