Open Stack

On 26 April 2013 04:27, Simo Sorce <simo at redhat.com> wrote:
> On Thu, 2013-04-25 at 17:19 +0100, David Chadwick wrote:
>> What happens in a very fast system if two sub-processes create a message
>> at the same time and therefore contain the same timestamp?
>
> Well, right now we use eventlet so no concurrency is really allowed.
> If we move to a truly concurrent system (something I actually hope we
> do) then we'll have to serialize how we get the timestamp. We'll
> basically need a single source of time that will just increment by one
> hundredth of a second or so if a second request comes in within the same
> hundredth of a second. Basically keep a high watermark in shared memory
> and use atomic updates to never get a dup.

We don't need to serialize : bring in snowflake (or a similar system).

-Rob

--
Robert Collins <rbtcollins at hp.com>
Distinguished Technologist
HP Cloud Services