[rdtsc]

> The future of server programming does not have parallel access to shared memory.

Yeah but it could be IO parallelism. There could be two instances of callback chains of sequence C1->C2->C3 started such that the the second starts before the first one finished. As in C1->C2 ran then C1 gets called again. If in those callbacks you update a data structure (a database record?), you now accessed that data in parallel. So you have to protect against that with some kind of a lock/mutex. Yeah context switching doesn't potentially happen at every assembly instruction, the granularity is much higher, but it is still there.

[dllthomas]

There's some need to synchronize, but hot damn is it simpler when you're dealing with sensible blocks of high-level statements than when you're dealing with out-of-order parts of assembly instructions.

[swift]

That's true, but personally I still don't find this model ideal because the synchronization points are implicit. The cleanest concept I know of for dealing with synchronization is transactions.