One aspect that may be of interest to you in regards to performance settings of adapters is maxConcurrentConnectionsPerNode.
maxConcurrentConnectionsPerNode – The maximum number of concurrent requests that can be
performed on the back-end application from the Worklight server node. This
maxConcurrentConnectionsPerNode parameter is set in the adapter.xml in the connectivity
entry.
There are two considerations when setting this parameter:
If there is no limitation in the back-end about the incoming connections then,
a "Rough" rule of thumb will be to set the number of connection threads per adapter
to be the number of http threads in the application server. A more precise rule
of thumb will be to understand the percent of requests going to each back-end and
set the number respectively.
The back-end may have a limitation on the incoming connection threads: In that case
we can have only BACKEND_MAX_CONNECTIONS/NUM_OF_CLUSTER_NODES connection threads where
BACKEND_MAX_CONNECTIONS is the maximum incoming connections define in the back-end
server and NUM_OF_CLUSTER_NODES is the number Worklight server nodes in the cluster.
You can also look into the Tuning Worklight Server documentation that covers some of the aspects you mentioned above:
https://www.ibm.com/developerworks/community/blogs/worklight/entry/tuning_worklight_server?lang=en