openstack team mailing list archive

[Soren Hansen <soren@xxxxxxxxxxx>]

2011/7/11 Ewan Mellor <Ewan.Mellor@xxxxxxxxxxxxx>:
> No, not string vs guid.  Current AWS IDs are 32 bits.  Being a small key
> space, this means that you either need to allocate them incrementally
> (implying a distributed transaction across the incrementer)

This is only a real problem if you insist on generating them in real
time rather than pre-allocate them. Each compute node could have pool
of thousands of ID's it could use as it pleased. That would still
allow for millions of compute nodes. The ID's could be centrally
assigned. Even if the central component that hands them out goes away,
a couple of thousand ID's should provide ample time for a replacement
to be spun up (or for the original one to come back).

> or you need to perform a collision detection (implying a distributed transaction across the
> database, or maybe even all the databases in all the zones).

Yeah, that would suck.

-- 
Soren Hansen        | http://linux2go.dk/
Ubuntu Developer    | http://www.ubuntu.com/
OpenStack Developer | http://www.openstack.org/