Spending Moore's Dividend
ftp://ftp.research.microsoft.com/pub/tr/TR-2008-69.pdf
This excellent paper from James Larus at Microsoft Research discusses how software abstractions and raised software expectations have essentially squandered the hardware advances of the last 30 years. Okay, perhaps squandered isn't the term, but the point is that software doesn't run any faster than it used to. James points out legitimate reasons as well as less legitimate reasons for this, and looks to the implications of increased parallelism on all of this.
My take: On one hand, I am all for meaningful software abstractions. I am also for language features that prevent us from shooting ourselves in the foot in obvious ways. I think we could do much better, however:
- Missed abstractions, particularly relations, has led to excessively complex and bloated software.
- Primitive data model - Today's software runs in a model based on allocating memory chunks and procedural APIs. This leads to countless redundancies in the software stack, as well as poor interoperability and optimizability.
- Physical data dependence - by separating the logic from the implementation, we could continually improve software performance without rearchitecting the logic.
- Memory utilization - Garbage collection introduces more problems than it solves. Value-based semantics and the relational model eliminated the need for GC. Virtual memory is, in hind-site, a bad idea. A much more effective architecture is to utilize memory as a cache for what are conceptually persistent data structures (e.g. DBMS architecture).
- Concurrency - again, if the programming model were shifted from references to memory to shared data structures, the issues with thread, process, and network concurrence are already solved. Much more highly concurrent application are possible in ways that are either transparent or opaque to the developer.
If you've ever sat there for a minute or two waiting for an application to swap back into memory so that it can close, you probably know something is fundamentally wrong with today's architecture.