Dear Govind and list,<br><br>Funny that just yesterday we faced the same issue (stressing with JMeter an OpenCms installation that included login into the workplace). The problem reason is that the method that writes user info (org.opencms.db.generic.CmsUserDriver.internalWriteUserInfos) first deletes the user info and then loops through the different user info nodes and writes them one by one. All this block is not synchronized, so concurrent accesses to inserting (after having both executions deleted) with the same pair "user_id" and "data_key" will produce a database key violation exception.<br>
<br>This issue is real but by concept it should also be unimportant, because for this issue to happen you have to have THE SAME USER login twice at the same time, and the same time means just in the code after deleting user info and while inserting. This is almost impossible for actual users to reproduce even if several logs in with the same username.<br>
<br>I guess it's up to Alkacon guys to evaluate the need of synchronizing that block of code or not. I hope this helped. Greetings,<br><br>Nacho Fernandez.<br>