Hello,
thank you for your message.
Please excuse me for getting back to you so late, I just got back from vacation.
One correction, the volume was not in a FAS2520 - which we also migrated - but in a FAS8040. Here it was on a pure SATA array, no flash pool and it worked.
We also use QoS and had the volume already in the "performance" group. - That should be enough, but it seems to be somehow due to the size.
We use OCUM and NAbox for monitoring; there are no abnormalities here, not even due to overloading of other volumes in the identical aggregate or something else.
Since the application that provides the data cannot be used properly at the moment by the users, access here is also currently only limited and a real comparison with the "old" performance data is not really possible.
In the meantime, we have also contacted NetApp support (couldn't find anything negative yet) and the manufacturer of the application software (who, however, has announced that they haven't made any changes yet) - but they are still searching...
It was just surprising that using a virtual file server, the separately provided data volume (which is located in the same aggregate as the volume of the SVM) does not cause any problems.
In my opinion, it can't be the StorageGRID either, where the cold data is located, where access might be a bit slower. The problem also exists when it is current, hot data (which is still on the SSD).
For now, I guess we'll have to wait for the application software vendor to get back to us.
I had also made this request because there might have been some parameter regarding the file size that I did not know so far.
Best regards
Michael