Reduce turbotunnel queueSize from 2048 to 512
After yesterday's deployment of io.Copy memory mitigations (#40177 (closed)), memory use has crept up above 90% again.
I recommend implementing the next most effective memory save
revealed by profiling: decreasing the turbotunnel queueSize.
This is a fixed block of memory that's allocated per connected client.
In dcf/snowflake@328f0f41 I've reduced the parameter from 2048 to 512. I don't know what effect this might have on performance, apart from reducing memory use.
Past discussion about queueSize: