Audit Trails and Impact on Documentum Performance

January 28, 2009

From my experience, we have to be careful about turning on audit trails in Documentum.  Turning on tracking for unnecessary events could lead to excessive audit trail creation in the database and will slow down the system.

For example, audit can be turned on for Sysobjects on several events. Two of these events are a bit confusing.

1) dm_getfile and 2) dm_fetch

While these two events sound similar at the first glance, their function is different.
1) dm_getfile occurs when a document is viewed or exported.  This is true “reading” of a document. You will want to turn this on to track which user downloaded/read this document.
2) dm_fetch occurs when webtop gets the documents attributes from the content-server.  This can occur when you perform a search or just browse to a folder.   This means that if you browse to a folder with 50 documents, it could potentially create 5o new audit trail records in the database!!  This is unnecessary, unless you have a strict security policy.

Watch out for this.  In our system, we turned on auditing for dm_fetch and ended up creating 8 million useless records and consuming all the database tablespaces.  After we realised what was happening, we turned off the auditing for dm_fetch and purged the unnecessary records, our system performance improved dramatically.

There are some excellent posts on EMC forums regarding this.  Do check them out.


Suggested Performance Testing Scenarios for Documentum (Webtop)

January 12, 2009

This is going to be a simple list:

– Login to Webtop (Due to authentication and display of cabinets/folders which involve ACL checks)
– Simple Search with 1 or 2 keywords (Due to FAST search engine and the ACL checks)
– Navigation to folders (object-list component could be very slow because of all the ACL checks, validation of actions, etc)
– Download a document (UCF can be slow)
– Upload a document (again UCF)

1) Rendering of HTML, Javascript, etc on a browser could take 1-3 seconds to display.
2) If you have Antivirus (Noticed with McAfee) which scans the HTML and .JS files, this will slow down the rendering further.

I will update this list if I come across any other scenarios.