Keep tempdb on separate physical disks from your critical application databases. Use the fastest disks available. If your platform supports solid state devices and your tempdb use is a bottleneck for your applications, use those devices. After you expand tempdb onto additional devices, drop the master device from the system, default, and logsegment segments.
Although you can expand tempdb on the same device as the master database,Sybase suggests that you use separate devices. Also, remember that logical devices, but not databases, are mirrored using Adaptive Server mirroring. If you mirror the master device, you create a mirror of all portions of the databases that reside on the master device. If the mirror uses serial writes, this can have a serious performance impact if your tempdb database is heavily used.