4 ms·
Nope, there isn’t a tradeoff; median latency isn’t affected. I don’t think you understand the code. The p50 is identical between a single read and the hedged
by lauriewired 6mo ago
Nope, there isn’t a tradeoff; median latency isn’t affected. I don’t think you understand the code. The p50 is identical between a single read and the hedged strategy.
The clflush is there because the technique targets data that will miss the cache anyway. If your working set fits in L1, you don’t need this.
Also, AWS Graviton instances absolutely do not expose per-channel memory controller counter PMUs. That’s why you have to use timing-based channel discovery.
The IBM z-system is neat! But my technique will work on commodity hardware in userspace, and you can easily only sacrifice half the space if you accept 2-way instead of 8+ way hedging. It’s entirely up to you how many channel copies you want to use.
Your reply was quite rude, but I hope this is informative.
- hedgehog 6mo agoI was just trying to reconcile his reply with the charts. Have you tested how this scales down for smaller systems, as one might find in on the management side of a network switch?
- jeffbee 6mo ago[flagged]
- zidders 6mo agoYou were rude. Be nice or don't post.
- rbanffy 6mo agoYou were rude for absolutely no reason. You could point out where you think the article comes short and make suggestions on how to improve it. With this approach, you achieved nothing. Being competent requires being knowledgeable AND getting things done. You might be knowledgeable, but you need to learn how to work with other people.
- intothemild 6mo agoI really hope you one day re-read these comments and understand just how horrible they are. For absolutely no reason. So yeah, you will be 'tone-policed' because you're clearly a very rude person.