Skip to content

[Backpressure] Avoid clearing the connection pool #1839

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Draft
wants to merge 2 commits into
base: main
Choose a base branch
from
Draft

[Backpressure] Avoid clearing the connection pool #1839

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
4cf95d9
Avoid clearing the connection pool on timeout and network error befor…
nhachicha Nov 12, 2025
778dbbf
update test
nhachicha Nov 12, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
13 changes: 13 additions & 0 deletions ...er-core/src/main/com/mongodb/internal/connection/DefaultSdamServerDescriptionManager.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -23,16 +23,20 @@
import com.mongodb.connection.ServerType;
import com.mongodb.event.ServerDescriptionChangedEvent;
import com.mongodb.event.ServerListener;
import com.mongodb.internal.diagnostics.logging.Logger;
import com.mongodb.internal.diagnostics.logging.Loggers;

import static com.mongodb.assertions.Assertions.assertFalse;
import static com.mongodb.assertions.Assertions.assertNotNull;
import static com.mongodb.assertions.Assertions.assertTrue;
import static com.mongodb.connection.ServerType.UNKNOWN;
import static com.mongodb.internal.connection.EventHelper.wouldDescriptionsGenerateEquivalentEvents;
import static com.mongodb.internal.connection.ServerDescriptionHelper.unknownConnectingServerDescription;
import static java.lang.String.format;

@ThreadSafe
final class DefaultSdamServerDescriptionManager implements SdamServerDescriptionManager {
private static final Logger LOGGER = Loggers.getLogger("connection");
private final Cluster cluster;
private final ServerId serverId;
private final ServerListener serverListener;
Expand Down Expand Up @@ -135,6 +139,15 @@ private void handleException(final SdamIssue sdamIssue, final boolean beforeHand
connectionPool.invalidate(sdamIssue.exception().orElse(null));
}
serverMonitor.connect();
} else if (beforeHandshake
&& (sdamIssue.relatedToNetworkNotTimeout() || sdamIssue.relatedToNetworkTimeout())) {
// clients MUST NOT clear the connection pool and MUST NOT mark the server Unknown when a connection establishment
// fails with network errors or timeouts
// TODO if we can detect reliably TLS handshake error (ex revoked certificate) we may choose to clear the pool and mark the
// server unknown
LOGGER.info(format("Connection pool is not cleared and server is not marked Unknown since we encountered a timeout or network"
+ " error before the handshake: %s", sdamIssue.exception().orElse(null)));
serverMonitor.cancelCurrentCheck();
} else if (sdamIssue.relatedToNetworkNotTimeout()
|| (beforeHandshake && (sdamIssue.relatedToNetworkTimeout() || sdamIssue.relatedToAuth()))) {
updateDescription(sdamIssue.serverDescription());
Expand Down
4 changes: 2 additions & 2 deletions driver-core/src/test/unit/com/mongodb/internal/connection/DefaultServerSpecification.groovy
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -234,7 +234,7 @@ class DefaultServerSpecification extends Specification {
]
}

def 'failed open should invalidate the server'() {
def 'timeout and network error should not invalidate the pool'() {
given:
def connectionPool = Mock(ConnectionPool)
connectionPool.get(_) >> { throw exceptionToThrow }
Expand All @@ -247,7 +247,7 @@ class DefaultServerSpecification extends Specification {
then:
def e = thrown(MongoException)
e.is(exceptionToThrow)
1 * connectionPool.invalidate(exceptionToThrow)
0 * connectionPool.invalidate(exceptionToThrow)
1 * serverMonitor.cancelCurrentCheck()

where:
Expand Down