NVFS
NVFS ( N on- v olatile f ile s ystem ; German: non-volatile file system ) is a development of PalmOne to the data and applications of a PDA to keep in non-volatile memory. The DiskOnChip flash memory is used as the memory module .
Because flash memory is much slower than conventional volatile RAM ( "volatile" RAM) caches palmOne the currently active application in a conventional 10 MB memory (this is comparable to the relatively slow disk and the fast RAM in the PC).
Benefits of NVFS
- The battery can be changed without data loss.
- Regular charging of the device is no longer necessary.
Disadvantages of NVFS
- Thanks to NVFS, each entry in Palm databases occupies an exact multiple of 512 bytes ; the memory is therefore used less efficiently than with volatile memories
- Since the active application is in the cache, in the worst case the data record that has just been processed can be lost despite NVFS
- Applications can take a little longer to start because they are first loaded into the cache. If this does not have enough free memory, other files have to be written back to the flash memory , which can also take a while.
PDAs with NVFS
PDAs with NVFS are the Tungsten T5 (256 MB in total), the Tungsten E2 and the Treo 650 (32 MB), the Treo 680, the Centro, the Treo 700w (128 MB), the Treo 700p (128 MB), the LifeDrive , the T | X (128 MB) and the Z22 (32 MB), all from PalmOne.
A similar system (persistent storage) is also used for all PDAs with the Windows Mobile 5.0 operating system .