Also make snapshot interval configurable

agent/agent.go

@@ -766,6 +766,9 @@ func (a *Agent) consulConfig() (*consul.Config, error) {
 	if a.config.RaftSnapshotThreshold != 0 {
 		base.RaftConfig.SnapshotThreshold = uint64(a.config.RaftSnapshotThreshold)
 	}
+	if a.config.RaftSnapshotInterval != 0 {
+		base.RaftConfig.SnapshotInterval = a.config.RaftSnapshotInterval
+	}
 	if a.config.ACLMasterToken != "" {
 		base.ACLMasterToken = a.config.ACLMasterToken
 	}

agent/config/builder.go

@@ -674,6 +674,7 @@ func (b *Builder) Build() (rt RuntimeConfig, err error) {
 		RPCRateLimit:                rate.Limit(b.float64Val(c.Limits.RPCRate)),
 		RaftProtocol:                b.intVal(c.RaftProtocol),
 		RaftSnapshotThreshold:       b.intVal(c.RaftSnapshotThreshold),
+		RaftSnapshotInterval:        b.durationVal("raft_snapshot_interval", c.RaftSnapshotInterval),
 		ReconnectTimeoutLAN:         b.durationVal("reconnect_timeout", c.ReconnectTimeoutLAN),
 		ReconnectTimeoutWAN:         b.durationVal("reconnect_timeout_wan", c.ReconnectTimeoutWAN),
 		RejoinAfterLeave:            b.boolVal(c.RejoinAfterLeave),

agent/config/config.go

@@ -195,6 +195,7 @@ type Config struct {
 	RPCProtocol                 *int                     `json:"protocol,omitempty" hcl:"protocol" mapstructure:"protocol"`
 	RaftProtocol                *int                     `json:"raft_protocol,omitempty" hcl:"raft_protocol" mapstructure:"raft_protocol"`
 	RaftSnapshotThreshold       *int                     `json:"raft_snapshot_threshold,omitempty" hcl:"raft_snapshot_threshold" mapstructure:"raft_snapshot_threshold"`
+	RaftSnapshotInterval        *string                  `json:"raft_snapshot_interval,omitempty" hcl:"raft_snapshot_interval" mapstructure:"raft_snapshot_interval"`
 	ReconnectTimeoutLAN         *string                  `json:"reconnect_timeout,omitempty" hcl:"reconnect_timeout" mapstructure:"reconnect_timeout"`
 	ReconnectTimeoutWAN         *string                  `json:"reconnect_timeout_wan,omitempty" hcl:"reconnect_timeout_wan" mapstructure:"reconnect_timeout_wan"`
 	RejoinAfterLeave            *bool                    `json:"rejoin_after_leave,omitempty" hcl:"rejoin_after_leave" mapstructure:"rejoin_after_leave"`

agent/config/runtime.go

@@ -905,6 +905,11 @@ type RuntimeConfig struct {
 	// hcl: raft_snapshot_threshold = int
 	RaftSnapshotThreshold int
 
+	// RaftSnapshotInterval sets the interval to use when checking whether to create
+	// a new snapshot. Defaults to 5 seconds.
+	// hcl: raft_snapshot_threshold = int
+	RaftSnapshotInterval time.Duration
+
 	// ReconnectTimeoutLAN specifies the amount of time to wait to reconnect with
 	// another agent before deciding it's permanently gone. This can be used to
 	// control the time it takes to reap failed nodes from the cluster.

agent/config/runtime_test.go

@@ -2422,6 +2422,7 @@ func TestFullConfig(t *testing.T) {
 			"protocol": 30793,
 			"raft_protocol": 19016,
 			"raft_snapshot_threshold": 16384,
+			"raft_snapshot_interval": "30s",
 			"reconnect_timeout": "23739s",
 			"reconnect_timeout_wan": "26694s",
 			"recursors": [ "63.38.39.58", "92.49.18.18" ],
@@ -2854,6 +2855,7 @@ func TestFullConfig(t *testing.T) {
 			protocol = 30793
 			raft_protocol = 19016
 			raft_snapshot_threshold = 16384
+			raft_snapshot_interval = "30s"
 			reconnect_timeout = "23739s"
 			reconnect_timeout_wan = "26694s"
 			recursors = [ "63.38.39.58", "92.49.18.18" ]
@@ -3412,6 +3414,7 @@ func TestFullConfig(t *testing.T) {
 		RPCMaxBurst:               44848,
 		RaftProtocol:              19016,
 		RaftSnapshotThreshold:     16384,
+		RaftSnapshotInterval:      30 * time.Second,
 		ReconnectTimeoutLAN:       23739 * time.Second,
 		ReconnectTimeoutWAN:       26694 * time.Second,
 		RejoinAfterLeave:          true,
@@ -4092,6 +4095,7 @@ func TestSanitize(t *testing.T) {
     "RPCProtocol": 0,
     "RPCRateLimit": 0,
     "RaftProtocol": 0,
+    "RaftSnapshotInterval": "0s",
     "RaftSnapshotThreshold": 0,
     "ReconnectTimeoutLAN": "0s",
     "ReconnectTimeoutWAN": "0s",

agent/consul/config.go

@@ -448,7 +448,7 @@ func DefaultConfig() *Config {
 	// Disable shutdown on removal
 	conf.RaftConfig.ShutdownOnRemove = false
 
-	// Check every 5 seconds to see if there are enough new entries for a snapshot
+	// Check every 5 seconds to see if there are enough new entries for a snapshot, can be overridden
 	conf.RaftConfig.SnapshotInterval = 5 * time.Second
 
 	// Snapshots are created every 8192 entries by default, can be overridden

website/source/docs/agent/options.html.md

@@ -360,7 +360,10 @@ will exit with an error at startup.
   for more details.
 
 * <a name="_raft_snapshot_threshold"></a><a href="#_raft_snapshot_threshold">`-raft-snapshot-threshold`</a> - This
-  control the minimum number of raft commit entries between snapshots that are saved to disk.
+  controls the minimum number of raft commit entries between snapshots that are saved to disk.
+
+* <a name="_raft_snapshot_interval"></a><a href="#_raft_snapshot_interval">`-raft-snapshot-interval`</a> - This
+  controls how often servers check if they need to save a snapshot to disk.
 
 * <a name="_recursor"></a><a href="#_recursor">`-recursor`</a> - Specifies the address of an upstream DNS
   server. This option may be provided multiple times, and is functionally
@@ -941,6 +944,9 @@ Consul will not enable TLS for the HTTP API unless the `https` port has been ass
 * <a name="raft_snapshot_threshold"></a><a href="#raft_snapshot_threshold">`raft_snapshot_threshold`</a> Equivalent to the
   [`-raft-snapshot-threshold` command-line flag](#_raft_snapshot_threshold).
 
+* <a name="raft_snapshot_interval"></a><a href="#raft_snapshot_interval">`raft_snapshot_interval`</a> Equivalent to the
+  [`-raft-snapshot-interval` command-line flag](#_raft_snapshot_interval).
+
 * <a name="reap"></a><a href="#reap">`reap`</a> This controls Consul's automatic reaping of child processes,
   which is useful if Consul is running as PID 1 in a Docker container. If this isn't specified, then Consul will
   automatically reap child processes if it detects it is running as PID 1. If this is set to true or false, then