Performance Questions and Poller Implementation in Project Loom

[Robert Engels]

Based on my issue the Helidon team has changed this for 4.0.1. It will no longer set the socket buffer sizes unless specifically configured to do so - which allows the OS network auto tuning to work. 

I fully expect this will make the performance the same. 

Thanks for all the input. 

> On Nov 10, 2023, at 6:51 AM, Alan Bateman <Alan.Bateman at oracle.com> wrote:
> 
> On 10/11/2023 12:05, Robert Engels wrote:
>> In the robaho version there is no setting of the socket send buffer - it uses the os default size. The 1mb buffer in user space is the same in both. Same with the baseline.
>> 
>> The floating buffer is what causes the ENOBUFS in OSX - Linux does not exhibit this issue.
>> 
>> That helidon is setting the kernel send buffer behind the scenes was not obvious to me.
>> 
>> I will try and configure both to be be the same and rerun.
>> 
> I see Daniel Kec has posted a code fragment in the github issue on how to configure it when using the webserver builder. So yes, it will have a default value when the connection is initially accept but it is being changed to 32k.
> 
> -Alan