Skip to main content

This content has been archived and is no longer being updated. Links may not function; however, this content may be relevant to outdated versions of the product.

Support Article

Index not picked up on PC_LINK_ATTACHMENT causing app slowness



When users are attaching Note/File to a work object it is generating thread dump and users are getting the unable to synchronize error.

Error Messages

Status fail
Message Unable to synchronize on requestor H18D6F747D28C3E9A28042CBA8DCCD2CA within 120 seconds: (thisThread = [ACTIVE] ExecuteThread: '47' for queue: 'weblogic.kernel.Default (self-tuning)') (originally locked by = [ACTIVE] ExecuteThread: '7' for queue: 'weblogic.kernel.Default (self-tuning)') (finally locked by = [ACTIVE] ExecuteThread: '7' for queue: 'weblogic.kernel.Default (self-tuning)')
Operator ID Unauthenticated or not available
Requestor ID No ID available
Timestamp Wed Nov 05 11:34:48 PST 2014
Engine Version PegaRULES 6.1 SP2 (coreBuild_060120_0161)

Steps to Reproduce

1.Login to the application
2.Create a case
3.Select Add or Edit Attachment from the Tools drop-down
4. Upload the file/note and hit submit
5. Users sees clocking on the screen and gets unable to synchronize error

Root Cause

The root cause of this problem is defect/misconfiguration in the PRPC operating environment.

The query to read attachment data from the DB was taking very long (few minutes). On analysis it was seen that the query was doing full table scans on the DB table even though there was an index available for it to use.

After the statistics were re-gathered, the query ran much quicker (fraction of second). The issue seems to have been caused by Adaptive Cursor Sharing feature in Oracle DB.


This issue is resolved by making the following change to the PRPC operating environment:

Regather stats for the table in the database and re-build indexes. On re-running the query was quick. Until query was run again, the explain plan was still the old one.

Published January 31, 2016 - Updated October 8, 2020

Was this useful?

0% found this useful

Have a question? Get answers now.

Visit the Collaboration Center to ask questions, engage in discussions, share ideas, and help others.

Did you find this content helpful?

Want to help us improve this content?

We'd prefer it if you saw us at our best.

Pega Community has detected you are using a browser which may prevent you from experiencing the site as intended. To improve your experience, please update your browser.

Close Deprecation Notice
Contact us