3 ms·

Please stop advocating for politeness over correctness. Sure hindsight help but regardless, a company such as Twitter should have experts at tracing that have t

• londons_explore 5y ago
  > a company such as Twitter should have experts at tracing In a big company, getting the person with the most skills to solve a problem to be the one actually tasked with solving the problem is very hard. This particular problem had many avenues to find a solution - and while I think my proposed route would have been quicker, if you aren't aware of those tools or techniques, then other avenues might be much quicker. When starting an investigation like this, you don't know where you're going to end up either - if it turned out that the performance cliff was caused by CPU thermal throttling, it would be hard to see in a scheduling trace - everything would just seem universally slow all of a sudden.
  • neerajsi 5y ago
    On Windows, we have the xperf and wpa toolset that makes looking at holistic scheduling performance, including processor power management and device io tractable. Even then, the skillset to analyze an issue like the one presented here takes months to acquire and only a few engineers can do it. We have dedicated teams to do this performance analysis work, and they're always in high demand.