After having the beta for a while I decided to do a clean install to 6.2.1. Formatted all my drives to BTRFS and started moving my media back.
So far all good, I am seeing the expected behavior on all my disks, checked them individually just to be sure, capping the LAN speed for the first 8-10GB (Ram caching?) and after that hovering to 60-65MB/s. Those transfers achieved with reconstruct write and no cache on the shares.
At some point during the move back, I believe when my main media share reached the one 3TB drive to 50% and switched to another drive I started seeing speeds hard to explain.
The file I copy to all transfers is 15GB,
Share to disk1, no cache, reconstruct write
Share to disk1, no cache, read-modify-write
Share to disk3, no cache, reconstruct write
Share to disk3, no cache, read-modify-write
Share to disk5, no cache, reconstruct write
Share to disk5, no cache, read-modify-write
Heavy drop on all the drives except disk3, who doubled the write speed compared to when it was below the 50% full mark. I'm guessing that have to do with doing the parity calculations alone, since the position on the parity is beyond the rest of the drives? In that case why does it take that much hit with read-modify-write?
As far as the rest goes is it normal to have that much of an impact when recalculating parity with the array drives empty vs with data on them? And whats up with the fluctuation? It goes from 20-30MB/s to capping the Gbit lan.
I have been puzzled for a couple of days with those numbers, any help will be appreciated.
storm-syslog-20161018-0031.zip
storm-diagnostics-20161018-0035.zip