One of our abinitio application is loading around 5 to 6 teradata tables concurrently using TPUMP utility.During the load time we are getting session block alerts.We have set the session parameter as maximum 4(sessions) and minimum 2(sessions) for each tables.please reply to this post if anyone knows the reason of why this session block occurs.
Can you please send me your TPump script? I will take a further investigation. Thanks!
--Ivy, TPump developer.
We are using Abinitio as a tool to load the data to these tables .It will write the script internally.We are using a component NCR store data to load these tables.We cannot view the scripts.
There could be row hash lock contention between sessions.
Please check if SERIALIZEON option is presented in the script. The SERIALIZEON option is useful when a TPump job is targeting multiple tables; SERIALIZEON could be used to reduce, and sometimes eliminate row hash lock when multiple SESSIONS are used.
Or you might want to try one session for each table to see this helps.
Thanks for your reply.I have made changes in my tool to load the tables serially.But that is affecting the perfomance during the run time.Is there any alternate way to load the tables concurrently without happening the session block?
How many sessions by default teradata will allocate for one table if we are loading it using TPUMP utility?Currently we have set maximum 4 sessions and minimum 2 sessions for each table when it loads concurrently.
There is no default value for Number os sessions; it must be specified.
If you want to load the tables concurrently, and the tables do not share the same primary index, the use of SERILAZEON option of the DML LABEL commnad is preferable. Please check TPump manual for more information.
In general, the TPump performance has variations in:
1. The data-loading environments.
2. The target table characteristics.
3. The structure and demographics of the data being loaded.
4. The different performance-related TPump options