Our IT department contacted me recently and asked if they should change the default TcpAckFrequency from 2 to 1 on SQL servers that I am managing - I manage the SQL part, they manage the server part. It is a MS setting that can be read about here: https://learn.microsoft.com/en-us/troubleshoot/windows-server/networking/registry-entry-control-tcp-acknowledgment-behavior
If I understand it correctly, it will cause the network to acknowledge each tcp segment and not only every second segment or when 200 ms elapses if no further segments are received.
They (the IT department) found that another application observed (a felt) increased responsiveness when this setting was changed on that application's back end SQL server, but I think they did not actually measure it with facts, but they swear it has seen a highly noticeable performance increase in the web application.
Does anyone here have any experience fiddling with that registry setting on SQL server machines?