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Stable Storage

At DIKU users (such as myself) normally have a home directory quota of 8Mb. Some privileged users have been granted additional 20Mb of disk space, making it a total 28Mb. Space for additional file information and space for file copies and/or logs are also required. A preliminary guess would be that a 100Mb cache size would suffice for a disconnected (see 2.2.3) day's work for (normal) users, e.g., students at DIKU.

Coda has reported that in their environment a cache size of 25Mb for one day of disconnected work or a cache size of 100Mb for a full week of disconnected work should suffice [42]. It must be remembered that they also cache system files requiring additional space compared to my environment. On the other hand, system files are not modified (at least they should not be) during disconnection, so they do not require additional space for file copies or logs. These facts suggest that the preliminary guess of 100 Mb is not totally off.

Nowadays, an additional 100 Mb of harddisk does not cost a fortune, in fact, harddisks with less than 500 Mb is seldom seen anymore.

The operating system and the usual applications that come with it also requires some space (remember that the mobile computer should be self-contained), but how much is entirely up to the user. For Linux it is somewhere between 100 Mb and 1 Gb depending on how much you need/want. Anyway, I will not consider it a concern of mine; I am only concerned with the available space for caching.


next up previous contents index
Next: Vulnerability Up: Mobile Computers Previous: Performance   Contents   Index

michael@garfield.dk
2000-10-13