I didn't realize HTrace was struggling in incubation. Maybe some of us can start participating? The project did start within Accumulo, after all. What does it need? I also wouldn't want to go back to maintaining cloudtrace.
I'm unfamiliar with OpenTracing, but it was my understanding that Zipkin was more of a tracing sink, than an instrumentation API. HTrace is actually listed as an instrumentation library for Zipkin (among others). On Tue, Feb 27, 2018 at 11:23 AM Sean Busbey <bus...@apache.org> wrote: > More things we should get ahead of for Accumulo 2.0.0: distributed tracing. > > Right now we have an awkward situation wrt HTrace support. We're using and > shipping htrace 3.1. It works okay for our internal uses, afaict. > > Hadoop 2.6 ships and uses HTrace 3.0. I believe this does not work with > 3.1. > > Hadoop 2.7 ships and uses HTrace 3.1, which means we can trace things down > through the hdfs layer, though I've never managed to get anything useful > out of trying to do so. > > Hadoop 2.8+ ships and uses HTrace 4.0, which isn't compatible with 3.1. > > Hadoop 2.9+ and 3.0+ ship and use HTrace 4.1, it doesn't work with 3.1 and > it's not clear to me if it works with 4.0. > > I *think* this means that we can only do tracing down into a single minor > release line of HDFS. > > Additionally, as of their January podling report[1] it looks like HTrace > is about ready to shut down as a project. In theory it could continue on > github or something after exiting the ASF incubator, but I don't see why > we'd expect an increase in activity; the project's been pretty idle for at > least a year. > > I really don't want to go back to maintaining cloudtrace. So what should > we do? Zipkin has some decent uptake[2]; they're still making regular > releases. Maybe just adopt OpenTracing[3] as a way to hedge against having > to do his again? > > YCSB is the Accumulo downstream with tracing that I'm most familiar with. > It relies on HTrace 4.1. I'm probably going to push that community to > abandon HTrace soon. (I was the one that pushed it to adopt HTrace in the > first place). I'd like to at least get tracing from YCSB through Accumulo > in the process. > > [1]: https://s.apache.org/uDHN > [2]: https://zipkin.io/ > [3]: http://opentracing.io/documentation/ >
