Thanks for your answers guys. I won’t defrag it, I’ll run Repair disk from disk utility again. Nothing else is using the FW800 bus, and nothing is daisychained.
I have another problem with the drobo, that might be linked to this one.
As said in my first post, I have one 500GB drive for Time Machine. When time machine does it’s initial backup to the sparsebundle on that partition, everything is okay. But then at some point it corrupts the sparsebundle, leading to an error 109 when it tries to mount. This usually happens when it’s been doing incrementals for a few days.
I’ve read some tutorials on how to fix the error, and I’m able to follow those steps and regain access to the sparsebundle. Only to have time machine corrupt it again the day after
Time Machine shows this behavior when backing up to the Drobo when it’s hooked up to my Airport Extreme base station. So I’m not sure wether the problem is the Airport Extreme, or the Drobo raid array, or the combination of both.
This happens when I let Time Machine create the sparsebundle, and when I let it back up to a sparsebundle created through the automator script floating around in this forum. BackUpMyFruit I believe it’s called.
Perhaps there’s something wrong with the initial format of the Drobo disk pack, that causes the backup to go corrupt and transfer/write speeds to be slow?