c) Penalties for incremental development

• The first penalty incurred by serialization (of which synchronization is a weak form), is that the benefits expected from distribution (see 1.1.1.) are ruined. A system using RPC introduces waiting, and thus does not scale up smoothly as it is being distributed. The system tends to close itself around an optimum size, which fights the spirit of supporting incremental development.
• The interaction between tasks introduced by locks causes even more severe problems, leading to dead-locks (and optionally live-locks, typically resulting from attempts to recover from dead-locks). The main problem for incremental development is that such situations are global to the whole system. The probability of dead-locks grows with the number of tasks. This again limits the size of any system below some difficult to compute but inescapable critical size. The schemes commonly considered to deal with dead-locks ([Goscinski91] distinguishes prevention, avoidance and detection / resolution) are global as well.
  The lack of appropriate information at the point of locking, prevents local detection and resolution. The key, in our analysis, is the lack of a proper scope within which to present this information.

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