Error (-48) message, and more...

Question

For the past two months I have been having problems with my Fifth-Generation 80 GB iPod that I purchased in March. I'd be playing music on it, and occasionally it would freeze up, either randomly (when a new track came on -- not specific tracks, so far as I could tell) or if I were to try switching menus. Usually though, as long as I would reset the iPod, it would return to normal working order (sometimes I'd get the "restore" message, but if I reset the iPod again, it would work fine). This happened a little more frequently as time went on.
Last week I decided to go through my iPod library to see if there were any corrupted files or anything, and found that in fact iTunes couldn't read about 2000 songs in the library. It was equally strange, because there was no pattern -- whole albums, random songs, songs that I had been listening to that morning, all apparently corrupted or missing. And also, songs that I knew had froze the ipod before seemed to be working just fine, with no exclaimation mark next to their entry.
At that point I had tried everything but restoring the iPod, so I went ahead and restored it. The first time, the pod and iTunes froze during the restore. After restarting my computer, I restored it, and then let iTunes automatically synch my library to the ipod. That froze up after loading about 600 songs (in a library of roughly 11500). I restored again, auto-synched, and it froze again. Restored once more, and manually added songs. It worked for a while but froze up. This cycle basically continued, not allowing me to add files to the ipod.
I took it to my local Apple store, and the guy that helped me out said it could be iTunes or perhaps corrupted files. I took it back home, and updated, than reinstalled iTunes. I tried adding files again, and it worked to a point, but after disconnecting the ipod, and then reconnecting it, files that originally showed up in the ipod as having been transferred successfully all of a sudden were not able to be recognized. The original files themselves are fine -- I checked and they play correctly and as far as I can tell are not corrupted.
I reattempted to add new files today, and the same problem occurred. However, there's a new twist -- now, whenever I plug my ipod into my computer and it shows up in itunes, if I click on anything within the ipod itself, i get a message that says "ipod can't be synched. an unknown error occured (-48)."
I apologize for the lengthy post, but I really don't know what else I can do. It kind of seems like I'm stuck with a really fancy paperweight now. If anyone gets through this monster and has ideas, please let me know -- if you need any more information, please just ask!
Thanks.
HP, 3 GHz, 504 MB RAM Windows XP
Windows XP
  Windows XP  

Answer 1

I would not blindly follow the storage adviser on this. It does its best, but it is just a basic algorithm. You have 88 million input rows, which is too large for a non-partitioned cube. The fact that the build takes up to 60 hours is proof enough of this. I think you will get a better build and query time if you have 10 or more partitions. The benefit of partitioning is twofold:
(1) It reduces the number of cells, or 'working set', that needs to be processed at one time. This makes it more likely that the data will fit into memory.
(2) You can build several partitions in parallel. This may or may not help in your case since it is a relatively small cube and you have only a dual core processor. But you should try 2 parallel processes.
Once you have tried partitioning, you should try compression again. It is unusual for query time to increase with a compressed cube (unless you have selected no precomputation). The recommended approach for compressed cubes is to use 'cost based aggregation'. I would start with 30% (with 0% for the top partition).
You may also look at the configuration of your system since OLAP has its own requirements.