ES备份至HDFS时，限速参数max_snapshot_bytes_per_sec设为0，但还是能做快照，是什么原因。而且设成其他值的话，感觉没起到作用。求大神指点

snapshotRateLimiter = getRateLimiter(metadata.settings(), "max_snapshot_bytes_per_sec", new ByteSizeValue(40, ByteSizeUnit.MB));



private RateLimiter getRateLimiter(Settings repositorySettings, String setting, ByteSizeValue defaultRate) {

        ByteSizeValue maxSnapshotBytesPerSec = repositorySettings.getAsBytesSize(setting, defaultRate);

        if (maxSnapshotBytesPerSec.getBytes() <= 0) {

            return null;

        } else {

            return new RateLimiter.SimpleRateLimiter(maxSnapshotBytesPerSec.getMbFrac());

        }

    }