* When making TLS connections with multiple [connection specs](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-connection-spec/), these are attempted in sequence until the TLS handshake succeeds.

### [Connections](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-connection/)

When you request a URL with OkHttp, here's what it does:

 * avoiding these options entirely, this class allows a connection to be attempted with modern
 * options and then retried without them should the attempt fail.
 *
 * ## Connection Reuse
 *
 * Each connection can carry a varying number of streams, depending on the underlying protocol being
 * used. HTTP/1.x connections can carry either zero or one streams. HTTP/2 connections can carry any

 * idleConnectionTimeout the timeout duration (in milliseconds) for idle connections
 *
 * <p>Methods:</p>
 * <ul>
 *   <li>{@link #expired()}: Handles the expiration of connections by closing expired and idle connections.</li>
 * </ul>
 *
 * <p>Logging:</p>
 * <ul>
 *   <li>Logs a warning if the clientConnectionManager is null.</li>
 *   <li>Logs a warning if an exception occurs during connection monitoring.</li>

 * **ExchangeFinder** chooses which connection carries each exchange. Where possible it will use the same connection for all exchanges in a single call. It prefers reusing pooled connections over establishing new connections.      

#### Per-Connection Locks

import okhttp3.internal.connection.ConnectionListener
import okhttp3.internal.connection.FastFallbackExchangeFinder
import okhttp3.internal.connection.ForceConnectRoutePlanner
import okhttp3.internal.connection.RealConnectionPool
import okhttp3.internal.connection.RealRoutePlanner
import okhttp3.internal.connection.RouteDatabase

/**
 * Manages reuse of HTTP and HTTP/2 connections for reduced network latency. HTTP requests that

 * limitations under the License.
 */
package okhttp3.internal.connection

/**
 * A policy for how the pool should treat a specific address.
 */
class AddressPolicy(
  /**
   * How many concurrent calls should be possible to make at any time.
   * The pool will routinely try to pre-emptively open connections to satisfy this minimum.
   * Connections will still be closed if they idle beyond the keep-alive but will be replaced.

 *
 *  4. If there's no existing connection, make a list of routes (which may require blocking DNS
 *     lookups) and attempt new connections to them. When failures occur, retries iterate the
 *     list of available routes.
 *
 * If the pool gains an eligible connection while DNS, TCP, or TLS work is in flight, this finder
 * will prefer pooled connections. Only pooled HTTP/2 connections are used for such de-duplication.
 *

plugins:
  - search
  - redirects:
      redirect_maps:
        # Redirect all feature pages to features/*
        'caching.md': 'features/caching.md'
        'calls.md': 'features/calls.md'
        'connections.md': 'features/connections.md'
        'events.md': 'features/events.md'
        'https.md': 'features/events.md'
        'interceptors.md': 'features/interceptors.md'
        'r8_proguard.md': 'features/r8_proguard.md'

                Arguments.of(WinError.ERROR_ACCESS_DENIED, "Access is denied."),
                Arguments.of(WinError.ERROR_REQ_NOT_ACCEP,
                        "No more connections can be made to this remote computer at this time because there are already as many connections as the computer can accept."),
                Arguments.of(WinError.ERROR_BAD_PIPE, "The pipe state is invalid."),

var globalLockGrid atomic.Pointer[grid.Manager]

// globalGridStart is a channel that will block startup of grid connections until closed.
var globalGridStart = make(chan struct{})

// globalLockGridStart is a channel that will block startup of lock grid connections until closed.
var globalLockGridStart = make(chan struct{})

func initGlobalGrid(ctx context.Context, eps EndpointServerPools) error {