How does Multiple shards per module support works in ODL nitrogen - opendaylight

Question

The module-shards.conf file mentions the following :
For Helium we support only one shard per module. Beyond Helium we will support more than 1
Have ODL Nitrogen and trying to use "module-shards.conf" like the following :
module-shards = [
{
name = "default"
shards = [
{
name="default1"
replicas = [
"member-1"
]
},
{
name="default2"
replicas = [
"member-1"
]
}
]
}
]
That seems to be working as karaf shows the 2 shards successfully created
for the same module "default". But how the data is distributed among
the 2 shards is not clear, can application control/decide which data goes in which of the module shards.
I am not clear how the application config tree data and the operational tree
data for a given module be stored under different shards for the same module.
If there are multiple shards for the same module, can application decide/control
which shard to use for storing a particular type of data. For example,
can application decide to store the config tree in "default1" shard
and operational tree in "default2" shard for the same module "default" ?
Is it possible to disable operational tree component for one of the shards of
a given module, say disable operational tree component for shard "default2"
of module "default" with 2 shards namely "default1" and "default2" ?

Answer 1

While it says for Helium only one shard per module is supported, that is still the case - support for more than 1 was never implemented. There hasn't been a use case for that. The shards are created but transactions are only routed to one of them (ie picks the first one that is found).