Multithreaded write support in Master

Question

1. We have an design where in we write synchronously at the master level. Since it is
bottleneck to usesynchronous write in a multithreaded environment. We have removed the
synchronous write,
which lead to too many DB_LOCK_NOTGRANTED Exception at master.
Note: write transaction timeout = 10secs ( which is too high)
Below PseudoCode will help in understanding above point.
HttpController
requestHandler()
     synchronous
     adapter.write(entity);
     //the adapter writes data to master inside a transaction with timeout value
10secs.
The questions are
a) Does BDB support multithreaded write at master?
b) If yes, is it something configurable?
2. In our new design, we have created an asynchronous threads(3 threads with queuecapacity of
20k) at the master level. 8-13 Replica(In production will have asynchronous threads(3 threads
with queuecapacity of 200k). What is the optimum number of threads that we can have at the
master level and queueCapacity?
For eg.
HttpController
requestHandler()
     aynchronousthreadexecutor.execute(entity, adapter);
     //asynchronous thread with 3 threads, 20k queueCapacity     
}

Answer 1

Corrigendum: Added information about BDB Version and few more helping information for this context.
Hi There,
We have the following questions w.r.t Multi threaded write at master.
1. We have an design where in we write synchronously at the master level. Since it is bottleneck to
use synchronous write in a multithreaded environment we have removed the synchronous write,
which lead to too many DB_LOCK_NOTGRANTED Exception at master.
Note: write transaction timeout = 10secs ( which is too high)
Below PseudoCode will help in understanding above point.
HttpController
requestHandler()
     synchronous
     adapter.write(entity);
     //the adapter writes data to master inside a transaction with timeout value 10secs.
The questions are
a) Does BDB support multithreaded write at master?
b) If yes, is it something configurable?
2. In our new design, we have created asynchronous threads(3 number with queuecapacity of 20k) at the
master level. Replica will have asynchronous threads(3 number with queuecapacity of 200k). In Production Replica count could
go upto 13.
a) What is the optimum number of threads that we can have at the master level
b) What would be ideal value qeueCapacity for the Executor (we use Spring Thread Executor)?
For eg.
HttpController
requestHandler()
     aynchronousthreadexecutor.execute(entity, adapter);
     //asynchronous thread with 3 threads, 20k queueCapacity     
Thanks.