You have a computer system which records stock levels for a warehouse. There

are two classes of operation that the system provides: updating stock level when

an item is added to or removed from the warehouse and generating a report that

lists the current stock level of every product in the warehouse and the total value

of the stock. There are, potentially, a large number of concurrent users of the

system. At the moment the system implements each request as a separate thread

with a mechanism to ensure that updates occur correctly (i.e. reading the current

stock level, computing the new level and writing the new value happens as an atomic

operation). There is no such mechanism in place for when the reports are generated.

You have been asked to prepare a document to assess whether it is necessary to

change the approach and what the effects would be.

Discuss this situation and propose and evaluate a potential solution. In particular,

you should identify potential problems with the current approach and what changes

you could make. You should specify the benefits, the effect on system load and the

effect on system responsiveness of these changes.