Re: Java Thread priority tuning for Quality-of-Service

2023-07-26 Thread Mark Miller
Yeah that's one area Java has always been a little weak with - I know of none Java systems where you can monitor requests and if one is taking much too long or two many resources, you can just hard kill it. I'm not sure there is much you can do java that's less ugly or more effective than just have

Re: Java Thread priority tuning for Quality-of-Service

2023-07-23 Thread Ilan Ginzburg
I also think we should gate at the entry point (decide to process a request, delay its processing or reject it) then do it as fast as possible (and potentially decide to reject and abandon during processing if the realization that it should have been rejected happens too late). Slowing down process

Re: Java Thread priority tuning for Quality-of-Service

2023-07-22 Thread Mark Miller
I think the problem is that it’s just extremely difficult to reason about. I think that’s really the root of the concern, and he’s generally working with code that’s likely close to hardware ideal - a thread count not much more than the number of cores at the high end. Here you have to reason about

Re: Java Thread priority tuning for Quality-of-Service

2023-07-22 Thread David Smiley
Thanks. I could see thread priority customization being used well in combination with rate limiting so as to mitigate a starvation risk. Yeah, I met Brian Goetz and have his excellent book. ~ David On Sat, Jul 22, 2023 at 3:20 AM Mark Miller wrote: > It’s a hint for the OS, so results can va

Re: Java Thread priority tuning for Quality-of-Service

2023-07-22 Thread Mark Miller
It’s a hint for the OS, so results can vary by platform. Not the end of the world but not ideal. A scarier fact is that Brian Goetz, pretty big name in Java concurrency, recommends against in general, noting that it can lead to liveness / starvation issues.