For all interests I found the problem:
For ervery process a table is created in the database and a lot of variables are stored as longblob or longtext in this table. For every column only the first 768 bytes are saved in ervery column the rest of the bytes stored in another page. The background for this failure is that MySQL only can stored 8000 Bytes per row. When too much variables of type longblob saved the row size will to big and MySQL throw the error 139.
The size will be exceed when too much longblobs are written in a row. The size of one longblob isn't interessted because only 768Byte are written.
Not only document variables are stored as longblob all complex objects are stored as longblobs.
The workarounds are reduce size of variables, reuse the variables (not a good design!) or change your database!
Another strategy to avoid this problem is to use sub-processes. Sub-processes are a preferred approach anyway to create re-usable services that can be leveraged in multiple applications and also make maintenance and support more efficient.
Another workaround is to use short-lived processes. When you use short-lived processes, no data is stored in the database. However, some service operations require long-lived processes (such as AssignTask operation that the User service provides).
Is there any other workaround to increase the size of the table row of the My SQL ..?
Since am facing the same error, since my process variable count is only 9 (4 list variables, 1 map variable and 4 xml variable).
Suggest me on this ..
One of my process consumes 20 variable of different kind. I don't think just 4 variables will cause this issue.
The warnings WBP-104 & WBP-105 are talks about the number of variables and number of actions recommendations respectively.
Look at the following link for more details.