[infinispan-dev] Hybrid locking scheme in ISPN 5.2.0

[Paolo Romano]

On 5/15/12 5:20 PM, Galder Zamarreño wrote:
> On May 15, 2012, at 4:58 PM, Paolo Romano wrote:
>
>> Hi Galder,
>>
>> Let me try to clarify this.
>> With Diego we have developed a system for
>> forecasting the performance (e.g. maximum throughput, abort rate, avg.
>> transaction execution time) of an ISPN application when it is deployed
>> on a cluster of a different scale (compared to the current one).
>>
>> We modelled using analytical techniques and machine learning the locking
>> and network-related behaviors of ISPN, but we did our work on ISPN 5.0
>> (replication mode), which used this "hybrid", partially local/partially
>> remote (and distributed=>  no primary owner).
>>
>> In other words, our performance prediction schemes won't work neither
>> for Optimistic nor for Pessimistic.
> Why do the predictions don't work?
Because the locking scheme has changed, hence its performance are 
changed, hence we are forecasting something different now :-)
>
> Where you guys somehow overriding some of the existing logic in 5.0 to track or record some data?
We were collecting additional statistics on tx usage. We have discussed 
this with Mircea, who was in our last meeting in Lisbon with us, and he 
has suggested how to re-implement that part to minimize intrusiveness of 
our software probes.

Indeed, as we were discussing with Mircea and Sanne, we would be glad to 
contribute these statistics to Infinispan as they may be useful not only 
for our performance forecasting techniques, but also for human-driven 
performance tuning. We are re-testing this code right now, and we will 
have a stable version at the end of the week.