https://bz.apache.org/bugzilla/show_bug.cgi?id=66513
Bug ID: 66513
Summary: Primary Key Violation using PersistentManager +
PersistentValves +
Product: Tomcat 9
Version: 9.0.72
Hardware: PC
Status: NEW
Severity: normal
Priority: P2
Component: Catalina
Assignee: dev@tomcat.apache.org
Reporter: vincent.liaut...@free.fr
Target Milestone: -----
Hi all,
when using PersistentManager + org.apache.catalina.valves.PersistentValve to
store session data in a Database table (in order to run Tomcat on containers
without sticky sessions) we get sometimes a "primary key constraint violation"
due to different thread that are badly synchronized.
When looking at source code, it appears that the usage of PersistentValve
assumes that we get only one request per session at any on time (and you
propose a filter parameter on the persistentValve component to avoid having
several requests at the same time).
However, in the case this filter is not complete (and so we get several
requests with the same sessionId at a time), the source code in
org.apache.catalina.valves.PersistentValve as well in
org.apache.catalina.session.DataSourceStore use a synchronized block to avoid
this problem but this synchronized block is useless because it uses a session
object that is different for each request.
You could solve this issue by using a static HashMap with keys and values
storing sessionId string, and using this sessionId string value as an object to
synchronize the blocks used to store the session in the DB table.
The process could be :
-If sessionId String not already store as a HashMap Key
-Store sessionId String as key and values
Synchronized(theHashMap(sessionId) {
....
....
remove it from the hashMap
}
That way you would really synchronize threads that use a same sessionId (and no
more) and would avoid those "primary key violation" errors.
Regards
--
You are receiving this mail because:
You are the assignee for the bug.
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscr...@tomcat.apache.org
For additional commands, e-mail: dev-h...@tomcat.apache.org
