Some tips for ATG Developers how to improve performance of the atg application and how to avoid typical mistakes

1. COMMON MISTAKES THAT AFFECT
PERFORMANCE

2. PROBLEM: SITE IS TOO SLOW

3. RESULT:ANGRYCUSTOMERS

4. HOW TO PREVENT PROBLEMS WITH
PERFORMANCE?
Frontend
Server’s
tuning
DB

5. SERVER’S TUNING
Apache
Gzip
• enable
mod_deflate.
Cache settings
• ExpiresDefault
"access plus 1
month“
Static content
JBOSS
trimSpaces
• it helps with
multiple blank lines

6. TIPS: REPOSITORIES
1. Do not use XML or HTML repositories
2. Configure repository item caching

7. TIPS: QUERIES
 Avoid SQLQueryForEach, SQLQueryRange and
other non-cached database querying
 Don’t use RQLQueryForEach if you have the
Repository Id you want, just use the
RepositoryLookup droplet.
 It's better to do more difficult queries in spite of
simple query and a lot of calculations on application
size

8. TIPS: TRANSACTIONS
 Do not access repository items outside of a
transaction
 ATG Commerce Order object must follow a specific
transactional pattern to avoid exceptions and
deadlocks, ConcurrentUpdateExceptions,
InvalidVersionExceptions
1. Obtain local-lock on profile ID.
2. Begin Transaction
3. Synchronize on Order
4. Perform ALL modifications to the order object.
5. Call OrderManager.updateOrder.
6. End Synchronization
7. End Transaction.
8. Release local-lock on profile ID.

9. TIPS
 The sortProperties parameter of *Range,
*ForEach, and Targeting* servlet beans
a sortProperties parameter provides an easy way to
sort items in an array.
 Avoid retrieving large arrays of data just to show a
few items: use the Range servlet bean to show
only a few items in the current page
 Example: Order History page

10. TIPS: OTHERS
 Verify that the PageFilter in web.xml is bound to
the right extension. Typically it's *.jsp, not /*.
 Pre-Compiling JSPs
 Recheck components scope
 Disable Performance Monitor
 Ensure that loggingDebug is disabled for all
components
 Disabling Document and Component Indexing
 /atg/devtools/DocumentIndex.enabled=false and
 /atg/devtools/ComponentIndex.enabled=false