In this commit, we make the gossip filter semaphore capacity configurable
through a new FilterConcurrency field. This change allows node operators
to tune the number of concurrent gossip filter applications based on
their node's resources and network position.
The previous hard-coded limit of 5 concurrent filter applications could
become a bottleneck when multiple peers attempt to synchronize
simultaneously. By making this value configurable via the new
gossip.filter-concurrency option, operators can increase this limit
for better performance on well-resourced nodes or maintain conservative
values on resource-constrained systems.
We keep the default value at 5 to maintain backward compatibility and
avoid unexpected resource usage increases for existing deployments. The
sample configuration file is updated to document this new option.