Transactional Memory

Posted Jun 4, 2009 20:08 UTC (Thu) by Frej (guest, #4165)
In reply to: Transactional Memory by wahern
Parent article: A look at two new languages: Vala and Clojure

I think your angle on (software) transactional memory is lockfree/nonblocking/wait-free stuff (the terms are somewhat vaguely defined imo).

But it's not the only point of STM (today). It's about safety and ease of concurrent programming on shared memory architectures.

Secondly, you missed the paper that inspired Software TM:
Transactional Memory: Architectural Support for Lock-Free Data Structures
Herlihy & Moss (1993)

Note that transactional hardware as an idea goes further back. But the above paper is pure hardware. Shavit and Toutiou later introduced Software Transactional Memory in the paper you posted.

So it is correct to distinguish between Transactional Memory and Software (assisted) Transactional Memory. Also, it does not make it pen and paper because the implementation uses locks. So surely STM exists, there are many implementations - The best are compiler/language assisted.