message: [AC] Increase AC thread pool size, up to a limit
diff: @@ -26,7 +26,7 @@ use network::{
  };
  use nextgen_crypto::ed25519::*;
  use std::{
  - cmp::max,
  + cmp::min,
  convert::{TryFrom, TryInto},
  sync::Arc,
  thread,
  @@ -58,7 +58,7 @@ fn setup_ac(config: &NodeConfig) -> (::grpcio::Server, AdmissionControlClient) {
  let env = Arc::new(
  EnvBuilder::new()
  .name_prefix("grpc-ac-")
  - .cq_count(unsafe { max(grpcio_sys::gpr_cpu_num_cores() as usize / 2, 2) })
  + .cq_count(unsafe { min(grpcio_sys::gpr_cpu_num_cores() as usize * 2, 32) })
  .build(),
  );
  let port = config.admission_control.admission_control_service_port;
  