Ok I see.
In allot of setups I see they are no longer running media servers but rather multiple masters that also do MSDP and then use AIR and replicate between sites for dr purposes.
So since I did not know your setup I was asking.
I would say 130 is a bare minimum and I can find the link if you want I know that with the latest releases we have updated the minimum requirements. At least for ram which you are still over the minimum. I do not know if we have updated the minimum requrements for underlying i/o. At 130 it is with degraded performance.
So the cache still runs the same in 7.5.0.5 as far as that goes. So there is something going on for sure with that and migrating the catalog could easily account for that.
However the thing you mention that is interesting to me is that the disk appears to be fine but that you have to run nbdevconfig to bring it up. Since the services associated with the dedupe storage are independent of netbackup this might suggest something going on with the netbackup processes were it is not properly showing the disk online once the disk comes up.
There may still be a delay with the dedupe pool coming up but netbackup should mark it as up once it is online.
if you don't have more like 200mb/s or more and you do quite a bit of backups with the system it could also be that your tlog queue could be getting behind. I have seen this often in busy environments. The reason this casues a delay is that when reading the cache into ram after it gets done reading the bin files it will then read through the tlogs to find updates to the cache. This can take a long time if your queue is large.
You could find out how many files are in your <storage location>\queue folder and let me know.
also under <storage location>\logs\spoold\spoold.log if you could find out how many transactions it is processing in about a 10 minute period that would be helpfull. This log file gives a time stamp and tells you how many transactions it processed so it's pretty easy to go through and see how much you are processing.
Thanks