I am finding that my DNS-325 NAS (tried both firmware v1.03 or v1.02) behaves very strangely when writing a large number of files to it from my iMac which is running OS-X 10.6. Furthermore, and it may be related to this, if I create sparsebundles to it and use a backup program such as SuperDuper to write to it, the transfers start fast enough but gradually slow down to a crawl; starting close to 30MB/s and slowing to a few KB/s. A backup of my Mac's data (600Gb) took a week!
Even deleting a sparsebundle is dead slow, taking many hours; the lights blink wildly at first then slow down to a couple of blinks every 30 seconds, taking hours to delete a 100GB sparse file. As far as I can understand, sparsebundles require many more I/O accesses than single large file transfers. The drive seems to do fine with SINGLE LARGE files (non-sparse) (ex: a single 20GB transfer to it worked cleanly at an average 28MB/s transfer rate).
I commented on another thread about transferring my entire iTunes music folder which contained 1000 sub-folders. In that case, the contents of some of the subfolders did not get transferred at all.
It's like there is an overflow issue with my setup or my DNS-325. Which is leading me to the comment about I/O overflows of some sort. In the case of my iTunes transfer, I succeeded in doing the transfer of my music only when I used ultracopier and forced it to reduce the transfer rate to less than 4MB/s.
I have AFP service enabled. I also tried with/without NFS service enabled. No difference.
I have run disk tests on the drives and they pass fine.
If anyone has a suggestion on how to diagnose this, it would be really appreciated.
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Topic: Slow throughput on DNS-325 with high number of sub-folders or sparsebundles (Read 3564 times)