Add a worker startup delay?

[druidance]

Hi,

Problem:
I'm using a SharedMemoryDict extension of a SharedMemory block that is accessible from different workers. Unfortunately, it's affected by a race condition when one worker is trying to allocate an already existing block of memory. This results in a situation when one or more workers cannot share information between each other.

Possible solutions:

1. (current) add a random delay in _get_or_create_memory_block of a SharedMemoryDict class
2. (desired) set a delay (in seconds) for worker-process forking via config or command-line option

What do you think?