Performance and scalability issues multi-country

[Pedro]

Hello,

I'm facing a new issue regarding EA performance over a database storage.

My company has two teams, one in Europe and another in USA. We have a single database (Postgres) storage, which is located in Europe. The USA team are facing HUGE lag when trying to access the elements in their EA (which is connected to the database in EU). Ping and speedtests show that the network should not be a problem here, since RTT is usually 135 ms, 200 maximum.

I would like some suggestions in what to explore here. What could the problems, and possible actions, be?

We thought about replicating our Postgress. However, a lazy sync strategy would imply in loss of integrity, and some different teams  work on the same element sometimes. Using a eager syncronization strategy I'm afraid I came back to the original problem.

Maybe the problem is the Postgres itself? Or maybe EA is not handling well the locks? The team are right now 15/5 (EU/USA) but should achieve 50/30 in no more than two quarters.

Any help is appreciated.

Best,

Pedro

[Dermot]

A couple of points: With WAN connectivity to an off-site repository it is reccomended that the response time on the WAN is under 100ms, however :
 - Have you tried the WAN Optimizer available with EA? This compacts data across the WAN connection
 - Each DBMS has very different throughput of data for the same transactions. I can't give any details on Postgres, but of those tested, MySQL gives the least throughput for the same transactions - you might try installing this and checking this against what you have.

If direct WAN connectivity is not an option check the alternatives (e.g. Version Control) listed in the Deployment Whitepaper available from:
http://www.sparxsystems.com/downloads/whitepapers/EA_Deployment.pdf

[Helmut Ortmann]

Hi,

think about

• Two local DBMS (Europe, USA)
• Using Version Control as a common data storage and more
• Checkin/Checkout to change something in EA
• Organize your Repository / Package Structure to avoid access conflicts

      (usually such a structure is robust)
[/list]

We had a similar problem. A slow VPN connection to our suppliers. It was in affect impossible to work on a central DBMS.

Then we changed the EA configuration to:

• One central DBMS
• Using Version Control (MKS, other like SVN would also work)
• Private *.eap file for remote users (another DBMS like my suggestion wasn't possible because of policy issues)
• Changes with Checkout, change, Checkin

After this change working was possible. I admit not everyone likes EA and Version Control. There are some issues. But in summary it works with our environment and requirements.

Have a look at the discussions in this forum. Be aware: It might be not an easy way. May be it's a good idea to get help from someone who had managed it before.

Best regards,

Helmut

[Reiner Saddey]

...
a single database (Postgres) storage, which is located in Europe. The USA
...

We've been using PostgreSQL (Amazon EC2 Ireland connecting from Germany) for a couple of weeks now and have been plagued by unacceptable response times, e.g. about 10 seconds for adding each and every new attribute to a class.

Out of curiosity and triggered by "MySQL & SQL Server models seem to cause less load than Oracle" I set up an Amazon RDS using MS SQL Server 2008. Now hold your breath:

Five times faster: 2 seconds instead of 10 - without any optimizations wahtsoever.

Maybe you should give it a try - it took just 2-3 hours for a novice like me (I haven't set up an EC2 / RDS before in my life).

[OpenIT Solutions]

Hi,

We faced similar performance problems as we have users in APAC, USA and Europe. WAN Optimizer will help a little. If you want to stick with a single database, Citrix server near the database will give the best performance increase.

If this doesn't work for you - then as mentioned above, i'd consider using a source control system as your central repository (without a database - the config guide is not very clear on this).

Regards,

Jon.

[qwerty]

Reiner, I wouldn't like to work with a system that has 2 sec response time. Definitely 5 times fast may seem to look like a great relieve. But honestly, I need instant access to model elements which is more like 2 ms  (IOW: factor 1000 rather than 5).

q.

[Reiner Saddey]

...
I need instant access to model elements which is more like 2 ms  (IOW: factor 1000 rather than 5).

You're right. I'm afraid this would require Sparx to introduce client-server architecture in order to eliminate those numerous time-consuming round-trips.
So in the end, it might be Remote Desktops again 

[qwerty]

I wonder how it would be to model UML on a 3270...

q.

[Dermot]

Reiner - in our tests MySQL came in under SQL server for size of data when non-optimised. So you might try MySQL with the WAN Optimiser. I am using this from home with minimal delay on 50-60 ms time lapse.
Do a Ping on the Off-site server IP address and check the timing.