val acquired =
        connection.withLock {
          when {
            requireMultiplexed && !connection.isMultiplexed -> false
            !connection.isEligible(address, routes) -> false
            else -> {
              call.acquireConnectionNoEvents(connection)
              true
            }
          }
        }
      if (!acquired) continue

    http2Connection.start()
  }

  /**
   * Returns true if this connection can carry a stream allocation to `address`. If non-null
   * `route` is the resolved route for a connection.
   */
  internal fun isEligible(
    address: Address,
    routes: List<Route>?,
  ): Boolean {
    assertLockHeld()

    // If this connection is not accepting new exchanges, we're done.