add override to ignore http errors

Author: Justin Fudally

go/base/context.go

@@ -119,7 +119,7 @@ type MigrationContext struct {
 	ThrottleAdditionalFlagFile          string
 	throttleQuery                       string
 	throttleHTTP                        string
-	ignoreHTTPErrors                    bool
+	IgnoreHTTPErrors                    bool
 	ThrottleCommandedByUser             int64
 	HibernateUntil                      int64
 	maxLoad                             LoadMap
@@ -579,7 +579,7 @@ func (this *MigrationContext) SetIgnoreHTTPErrors(ignoreHTTPErrors bool) {
 	this.throttleHTTPMutex.Lock()
 	defer this.throttleHTTPMutex.Unlock()
 
-	this.ignoreHTTPErrors = ignoreHTTPErrors
+	this.IgnoreHTTPErrors = ignoreHTTPErrors
 }
 
 func (this *MigrationContext) GetMaxLoad() LoadMap {

go/cmd/gh-ost/main.go

@@ -106,7 +106,7 @@ func main() {
 	throttleControlReplicas := flag.String("throttle-control-replicas", "", "List of replicas on which to check for lag; comma delimited. Example: myhost1.com:3306,myhost2.com,myhost3.com:3307")
 	throttleQuery := flag.String("throttle-query", "", "when given, issued (every second) to check if operation should throttle. Expecting to return zero for no-throttle, >0 for throttle. Query is issued on the migrated server. Make sure this query is lightweight")
 	throttleHTTP := flag.String("throttle-http", "", "when given, gh-ost checks given URL via HEAD request; any response code other than 200 (OK) causes throttling; make sure it has low latency response")
-	ignoreHTTPErrors := flag.Bool("ignore-http-error", false, "ignore HTTP connection errors during throttle check")
+	ignoreHTTPErrors := flag.Bool("ignore-http-errors", false, "ignore HTTP connection errors during throttle check")
 	heartbeatIntervalMillis := flag.Int64("heartbeat-interval-millis", 100, "how frequently would gh-ost inject a heartbeat value")
 	flag.StringVar(&migrationContext.ThrottleFlagFile, "throttle-flag-file", "", "operation pauses when this file exists; hint: use a file that is specific to the table being altered")
 	flag.StringVar(&migrationContext.ThrottleAdditionalFlagFile, "throttle-additional-flag-file", "/tmp/gh-ost.throttle", "operation pauses when this file exists; hint: keep default, use for throttling multiple gh-ost operations")

go/logic/throttler.go

@@ -291,8 +291,10 @@ func (this *Throttler) collectThrottleHTTPStatus(firstThrottlingCollected chan<-
 
 	_, err := collectFunc()
 	if err != nil {
-		// If an error occurs during the HTTP throttle check, let's throttle to be safe
-		atomic.StoreInt64(&this.migrationContext.ThrottleHTTPStatusCode, int64(-1))
+		// If not told to ignore errors, we'll throttle on HTTP connection issues
+		if !this.migrationContext.IgnoreHTTPErrors {
+			atomic.StoreInt64(&this.migrationContext.ThrottleHTTPStatusCode, int64(-1))
+		}
 	}
 
 	firstThrottlingCollected <- true