Increase min threshold to 2

Author: fbockaj

config/config.go

@@ -65,8 +65,8 @@ func (b Base) validate() error {
 	if b.SetSize < 2 {
 		errs += "\tset_size must be 2 or higher\n"
 	}
-	if b.Threshold < 1 {
-		errs += "\tthreshold must be 1 or higher\n"
+	if b.Threshold < 2 {
+		errs += "\tthreshold must be 2 or higher\n"
 	}
 	if b.StartRank < 1 {
 		errs += "\tstart_rank must be 1 or higher\n"

config/config_test.go

@@ -41,7 +41,7 @@ func testInvalidBase(t *testing.T, base Base) {
 	base.SetSize = testConfig(t).Base.SetSize
 
 	// Invalid Base.Threshold.
-	base.Threshold = 0
+	base.Threshold = 1
 	err = base.validate()
 	assert.Error(t, err)
 	base.Threshold = testConfig(t).Base.Threshold

config/templates/base.toml

@@ -18,7 +18,7 @@ set_size = 2
 # a rank update in the set.
 # This value must be the same across all validators
 # in the set.
-# Must be 1 or higher.
+# Must be 2 or higher.
 threshold = 10
 
 # Rank of the validator on startup.

types/signctrled.go

@@ -139,6 +139,8 @@ func (bsc *BaseSignCtrled) Missed() error {
 		// that the next block will not contain the validator's signature. This is due
 		// to a block containing the commit of the previous height which we know wasn't
 		// signed. Therefore, skip ahead.
+		// This is also the reason why the minimum threshold for blocks missed in a row
+		// is at 2.
 		bsc.currentHeight++
 		return ErrThresholdExceeded
 	}