The proxy is unresponsive to web traffic, but the admin gui and SSH are accessible. When checking https://<proxyurl>:8082/http/statistics, you find the Maximum acceptable concurrent client connections and Currently established client connections are the same, or the high water mark indicate this has been maxed out in the past. If https://<proxyurl>:8082/tcp/connections is checked for a correspondingly high number in the summary, many less connections are reported than workers. It is expected that these are somewhat close in value.
Clients reach a blank page. Refreshing the page may or may not load the page.
ProxySG or ASG
HTTP maximum workers has been reached
In principle items that allow the connection to drop when it is finished, but keep the client worker busy should be examined. Global tracing or tracing of many popular URLs can cause the policy trace queue to fill, and the client worker will not be released until writing the policy trace has completed, even if the connection has finished.