Pauses whilst streaming video files

I bought my Drobo-FS to replace an existing USB Drobo that I was using for media storage. The media copied across without any issue and I can see the Drobo-FS in the Drobo Dashboard OK however when I play any video files from the Drobo-FS on my Mac Mini I get pauses and stuttering (sometimes up to a minute) during playback.

These pauses seem to be intermittent during each file, but it happens with every file I play. If I copy a file to another iMac and play it from there it plays fine, so I know my gigabit network and switches are OK.
I only get the stuttering when playing back from the Drobo-FS.

I have tried disabling DroboApps, increasing the sleep timeout, but the problem remains.

Any ideas?

I’m using:
Latest firmware & dashboard for Drobo-FS
Gigabit ethernet & switches/router
No WiFi involved at all

For how long have you had the new Drobo? I experienced the same thing with lossless music files. Then after about 3-4 weeks it suddenly started to run flawlessly. I think the Drobo FS needs some time to put everything in order after a large amount of data has been copied to it.

I’ve had it since August and I copied about 2.5TB onto it as soon as it was built, so I would hope that by now it should have sorted itself out.

Does anyone know if there is any logging available on the Drobo? Then maybe I could spot some common event in the logs when the slowdowns occur.

As far as I can tell, the diagnostic files you can generate in Dashboard collects all the of the pertinent logs from the device (after the big encrypted section). Does the Drobo keep transferring data at times like this, or does it stop entirely? I had a bad unit that would cease all data transfer for 30 seconds or so every so often - activity light would be solid and throughput was zero. Might want to see what your throughput graph looks like when it occurs (a variety of utilities can do this - I like iStat Menus personally), and visually see if the lights on the Drobo are doing anything strange.

I’m having the same issue. Choppyness on video files. I’m tempted to change the MTU size on the network tab but i don’t know if I should.

I’d appreciate some advice.

Have you guys seen this thread about file fragmentation and the impact on performance?

It seems that the FS handles file fragmentation not so gracefully.

I did see that thread, but I wasn’t sure if it really applied to my case.
My data was copied over in one block when I first built the Drobo (it had 5 x 2TB drives in since day 1) so I would think that file fragmentation shouldn’t be an issue on this drive. I don’t run any torrent stuff on it, and I don’t use any Drobo apps.

I have a support ticket opened, and they have sent my diagnostics to the US team for investigation (I’m in the UK).

I’m starting to think about swapping back to a Drobo with a direct connection again, like a Drobo S, only then I’ll have to copy all my data over again!

Are you sure? I think some models are disk-pack compatible, i.e., you can take the whole disk pack from one to the other transparently.

Disclaimer: I’m not sure this is the case between the S and FS, so make sure to ask DR for clarification.

I did mention this to the DR support guy I spoke to, and he said they weren’t compatible. I remember seeing a chart or something that specified which models were disk-compatible with each other but I haven’t been able to find it since.

Here is the Page you are looking for http://www.drobo.com/migration/.

This page shows how to migrate your data from one unit to the other. Some of them the Drive Pack can be moved over and others you have to transfer the data.