After disabling useACK on an HF internal events get lost und

[DATEVeG]

Hi Splunk community,
we have an Heavy Forwarder which mostly ingests syslog data via tcp. The volume of ingested data is rather constant.
In order to check whether we could get could more performance we disabled useACK in the outputs.conf of the HF.
We were quite surprised that instead of increasing throughput by saving overhead, we observed a sharp drop in ingestion, including events from the internal logs of the Heavy Forwarder.
We went back enabling acknowledgement after an hour.
Can you give us some advice, that could explain this behvaiour?
Could this be a hint, that there's a deeper problem in out Splunk infrastructure that is smoothed out by the acknowledgement feature?
Thanks in advance!
Kindly regards,
Jens Wunder

[Pawlub1]

Hi,

I am troubleshooting a thruput issue regarding syslog feeds that have decreased in the total events by 50% as well as erratic metrics and was wondering if your question or observation has every been confirmed whereby the useACK is disabled in outputs.conf file a decrease in events takes place. 

It is counter intuitive that the disabling of useACK decreased thruput, but would really like to know if you finally got confirmation of your problem.