On 20130209 4:37 , Andrei Savu wrote:
On Sat, Feb 9, 2013 at 4:44 AM, Paul Baclace <[email protected]> wrote:
Do you have any rough idea of state transition latency and throughput you
get when using Activiti and how this compares to using Whirr/jclouds in a
single process?
Is this important? During pool creation most of the time is spent in loops
waiting for external services. We try to keep each activity as short as
possible to avoid long running transactions.
The reason I ask is that although Activiti has good support for designing
processes and programmatic control of the engine, it is necessarily DB
transaction limited. An obvious alternative design is to use something that
is actor based which can run entirely in RAM. I admit that an actor control
system would make it harder to trace what happened, compared to business
process control which is very much oriented toward human-in-the-loop.
I think it's going to take while for us to hit that limitation. I see good
performance even if we are using an embedded H2 database - it should work a
lot better with a PostgresSQL server. It's true that Activiti is oriented
towards human-in-the-loop processes but it works well also for unsupervised
ones.
As long as the orchestration is at the appropriate granularity (not
micro-managing), then using Activiti should be fine. Another thing it
can do that is more challenging for a single machine actor system is
preserve state across controller restarts.
Paul
