EA over WAN (performance issues)

[Dave_Bullet]

Thanks Dermot,

However EA doesn't need to (and shouldn't) do 100 database selects for a diagram with 100 elements on it.  This is what happens on MS SQL Server.  I have a MySQL to try incase EA employs a DB factory and different flavours of RDBMS are handled differently.

Also note - my SQL Server test was on EA6.5 - I will profile EA7.1 to see if it still does that (but I would put money on it that it still does  

Cheers,
David.

[«Midnight»]

Please let us know what you learn Dave.

This has been dogging us for a long time (as you know ever so well). I'm looking at a scenario where replication may be the only solution, but that does not make me happy.

[Perhaps we should discuss how replication works as EA and the schema have evolved, but on another channel.]

David

[Martin Terreni]

Regarding the configuration control. we work with a mesh of both DB and CC.
Our lan users us DB while our WAN users use CC. All of our packages in DB are also under CC and it works good, i thi we'll stick to it (also it allows to take work offline to our customer sites).

regarding:

Please note however EA is broken when it comes to diagram copy and paste as it does a "select *" and then crashes (due to the extra columns SQL Server adds to EA base tables to support replication).

This worries me very much, it isvery importnat that EA support replication. What does Sparx say about it?

For SQL Server we use merge replication. .

How does it work for you, did you have any special problems?
It is important inpout, thanks for sharing.

Martin

[Dave_Bullet]

Hi Martin,

I remembered you asked me for a copy of the modified SQL Server base script to suit replication.  I hope I sent it to you!

Our replication works ok.  Key thing is to configure each SQL server where identity values are used (ie. t_object.object_id) to use non-overlapping ranges so you don't get primary key clashes on the merge (ie. users on different replicas create a new object at the same time).  You configure this as part of the publication setup so that each subscriber gets issued a "chunk" of identity values.  This is done on a per article (= table) basis.

I have not comprehensively tested all EA features to see what works / doesn't work on replication.  ie. checking in and out of version control.  I fear there will be a lot more things that dont work.  To be fair to Sparx - SQL server replication isn't officially supported.  I think for true global scalability - they will need to eventually in the product.

If there are any admins from some really large organisations - feel free to chime in here and tell us your deployment model and number of users.

David (Midnight) - Citrix seems to work ok - so that is another option to get your EA instance closer to your database for better performance.  Other option is RDP / TSC for a small number of users.

Cheers,
DAvid.

[Martin Terreni]

Thanks, that is a good help [smiley=thumbsup.gif]

[Dave_Bullet]

Both 7.0 (build 817) and 7.1 (build 827) perform a lot less queries to open a diagram than previous (ie. 6.5 and before) versions.

For example,
A diagram with 100+ elements generates 29 queries to the database to open and takes approx 8 seconds
A diagram with 3 elements generates 20 queries to the database to open and takes approx 2 seconds.

The above is to a SQL server literally in the next room (therefore low latency) - so would represent a best case scenario in our distributed user environment.

On the large diagram - EA does some processing (about 3 seconds worth) after the first 20 queries - something not done with the second diagram.  Probably rendering the shapescript on the 100 elements in the diagram.  I can accept that.

Opening a large model though is still painfully slow.  Most of this is within EA not database queries.  93 are issued over the period of opening the model which takes a couple of minutes.

David.