diff --git a/dialoptions.go b/dialoptions.go index f5453d48a53f..efb3f0f24939 100644 --- a/dialoptions.go +++ b/dialoptions.go @@ -518,6 +518,8 @@ func WithUserAgent(s string) DialOption { // WithKeepaliveParams returns a DialOption that specifies keepalive parameters // for the client transport. +// +// Keepalive is disabled by default. func WithKeepaliveParams(kp keepalive.ClientParameters) DialOption { if kp.Time < internal.KeepaliveMinPingTime { logger.Warningf("Adjusting keepalive ping interval to minimum period of %v", internal.KeepaliveMinPingTime) diff --git a/keepalive/keepalive.go b/keepalive/keepalive.go index 34d31b5e7d31..eb42b19fb99a 100644 --- a/keepalive/keepalive.go +++ b/keepalive/keepalive.go @@ -34,15 +34,29 @@ type ClientParameters struct { // After a duration of this time if the client doesn't see any activity it // pings the server to see if the transport is still alive. // If set below 10s, a minimum value of 10s will be used instead. - Time time.Duration // The current default value is infinity. + // + // Note that gRPC servers have a default EnforcementPolicy.MinTime of 5 + // minutes (which means the client shouldn't ping more frequently than every + // 5 minutes). + // + // Though not ideal, it's not a strong requirement for Time to be less than + // EnforcementPolicy.MinTime. Time will automatically double if the server + // disconnects due to its enforcement policy. + // + // For more details, see + // https://github.com/grpc/proposal/blob/master/A8-client-side-keepalive.md + Time time.Duration // After having pinged for keepalive check, the client waits for a duration // of Timeout and if no activity is seen even after that the connection is // closed. - Timeout time.Duration // The current default value is 20 seconds. + // + // If keepalive is enabled, and this value is not explicitly set, the default + // is 20 seconds. + Timeout time.Duration // If true, client sends keepalive pings even with no active RPCs. If false, // when there are no active RPCs, Time and Timeout will be ignored and no // keepalive pings will be sent. - PermitWithoutStream bool // false by default. + PermitWithoutStream bool } // ServerParameters is used to set keepalive and max-age parameters on the