Navision Attain Cluster and SQL Server questions?

dwainek@sporthaley.com

We will be implementing Navision Attain 3.6 over the next 6 months. I have some questions for those experienced.

Q: Can Attain run on a two node cluster with Windows 2000 Advanced Server? I have read that Axapta can cluster but haven’t found anything on Attain.

Q: If running SQL Server, do clients access the db direct or do they go through the Navision service? If through the Navision service, could this service be distributed as a middle tier on a separate box allowing SQL Server dedicated resources?

I’ve been told that performance suffers moving to SQL Server. Couldn’t this lag be eliminated with a properly tuned db? Since Attain only uses one CPU, I find it hard to believe that SQL Server running multiple CPU cannot outperform Navision db unless the SQL db was poorly designed.

Q: Have those that converted to SQL Server seen decreases in performance? Have the issues been resolved?

Thanks in advance.

Dwaine

kraxmo

Hi Dwaine,

Regarding questions 2 and 3, I tried going to Attain 3.1 SQL last summer and encountered multiple locking problems during the first 3 weeks of implentation with 70+ users. Reservation table locking was a primary concern when entering sales orders while processing warehouse assignments and production orders.

It seems that Navision adopted a pessimistic locking strategy in porting their code to SQL. They sacrificed concurrent update speed offered by row-level locking for ultimate transaction safety that table/page locking offers. It was their solution for 3.1—hopefully future versions will optimize both object and SQL interfaces to take better advantage of the SQL product while maintaining the consistently high transaction level security we expect from native. (Note: if anybody has a better explanation or newer information, I would love to hear about it!)

Our Solutions Center could not resolve the problem as it had to do with low-level C/SIDE (and below) coding. We were forced to go back to native 3.1 as the SQL version just did not perform. We were running on a dual Pentium III server with lots of RAID and RAM, but the locking problems were affecting our ability to conduct business (up to 30 minute delays for our customer service department.) We are currently planning to test SQL again but are in need of a good client testing tool that can simulate multiple users with macro/scripting capability.

If you have more than 20 users, I recommend that you stress test prior to deployment.

dcintron

I had an idea to test overcoming the SQL reservation entry bottleneck, which was to install a NAS to route all reservation requests through using a table queue. You might try this with a non-NAS client to see if it will work, but it will take some coding just to test. If successful, there are a LOT of people who could use this solution.
Dave

dwainek@sporthaley.com

Thanks for the insight. I hope they did away with table locking in current version. They shouldn't port to any dbms if they don't trust the db’s ability to handle locking (or is it that they don’t trust themselves). Especially if they are locking early in the transaction rather than at commit. I have been told that the current db for 3.6 has been redesigned. Have you heard this as well?
I would imagine most of the bugs will be worked out in the early future with Microsoft pushing SQL server. The MS engineers have probably dissected the C/side db and client by now. With future integration of .Net framework, Attain should soon be optimized for SQL server. With limited knowledge of Attain, I can just hope this is the case.
I’ve been told recently that a Navision service doesn’t run when using SQL server, which inherently allows Attain to run clustered.

dcintron

Hi Dwaine,
I'm sure Navision has not changed their SQL client. I spoke personally with Robert Miller last year when I was at the Commerce Portal Class, and the situation is exactly what Kraxmo says. Until MS rewrites SQL to support SIFT, and MS/Navision rewrites the SQL Client as you say, Navision on SQL will perform like an overweight basset hound.
Dave Cintron
SCS

kraxmo

Woof-woof!!!