Sharing the variable across parallel executions for write operation

Hi Team,

In camunda BPMN do we have any palceholder or way to store variable which can be used(write operation) by multiple parallel threads/processes at the same time.

In my case i have parent process. That parent process is having multi-instance loop(parallel) and that loop is calling call activity bases on some list object.

Now i want to have single process variable to be accessed by all child activities triggered parallely for write operation. and i want to access that variable at parent process to read all the data written by different child processes.

Pradip Patil