For the moment, we allow one writer at a time, but unbounded (I think) readers. The only locks taken are for arithmetic operations; no locks are held while per

For the moment, we allow one writer at a time, but unbounded (I think) readers. The only locks taken are for arithmetic operations; no locks are held while performing I/O or even memcpy(2). You can read more about that bit in the paper about our caching architecture on the wiki. Eventually, we will allow multiple writers, and use some form of STM for that; we just haven't gotten to it yet. If you'd like to speak interactively on this, shoot me an email.