When Uptime Infrastructure Monitor connects to an ESX server to collect performance data, it registers a unique connection to the host API. This can cause an increase in log file sizes on the ESX server as each poll (e.g. every 5 minutes) will generate a new connection log message.
This behavior is normal and cannot be modified from the Uptime Infrastructure Monitor application. However, you may be able to adjust your ESX server logging parameters to limit these entries.