Missing or Truncated? By default Splunk default maximum line length is 10000, in bytes.
If your event is more than the default value you can increase the TRUNCATE value in props.conf but never ever set it to 0.
Make sure that you set properly the props.conf of the sourcetype of that data.
Check splunkd.log for messages such as "AggregatorMiningProcessor" to know more what's happening