If it is an on going error message then it could lead to performance problems when searching that index.
It means that all your buckets for a certain index are filling to their max size very quickly. You can change the bucketsize from auto (700MB per bucket) to auto high volume(10GB per bucket) to resolve this.
You can use |dbinspect index=<indexName> to inspect the bucket size for the suspect index
maxDataSize = auto_high_volume
https://docs.splunk.com/Documentation/Splunk/9.0.1/Admin/Indexesconf