@Jungtaek, We did some tests on codahale metrics, compared to meters/histograms, counters are quite fast. So we mainly focused on the optimization of meters and histograms (they are indeed very slow) including double sampling, changing the clock from ns (System.nanoTime) to ms, etc. You can take a look at the "com.alipay.dw.jstorm.example.sequence.bolt.TotalCount" class of our sequence-split-merge example code, as the client code entry to metrics. After that, you may dig to TopologyMaster class, which is still part of a topology, and then to TopologyMetricsRunnable, which is a part of nimbus server, finally to MetricUploader plugin, this is where the metrics interfere with our "metrics server". Still, there're some nits in the code, but I think that should be no big problem.
I'd also like to point out that our "metrics server" is not strictly a real metrics server, since most of the duty lies on nimbus server and topology master, it's more appropriate to call it metrics storage. The main reason for this is that we don't want to make a heavy-weight metrics server out of JStorm, and this makes us very easy to maintain (we have teams that specifically maintain HBase/OTS in Alibaba since they're so commonly used in production). On Mon, Mar 21, 2016 at 10:54 PM, Jungtaek Lim <[email protected]> wrote: > Thanks Cody and Bobby for the explanation. > > Cody, > I took a look at design doc and looks promising, especially it doesn't do > sampling when metric type is 'counter'. As far as I heard (I didn't try it) > it becomes huge performance hit in Apache Storm when we change sample rate > to 1.0. > Could you guide the entry point of metric feature in JStorm to dig into? > > And just a curiosity, did you consider extracting metric feature (which is > done with TopologyMasters and Nimbuses) into separate component? > I understood your mention to 'metrics server' as separate component, but > after seeing design doc, feature seems to be implemented on Nimbus. > > Thanks, > Jungtaek Lim (HeartSaVioR) > > 2016년 3월 19일 (토) 오전 1:25, Cody Innowhere <[email protected]>님이 작성: > > > JStorm has provided a MetricUploader interface, which is similar to > > IMetricsConsumer in storm, and the underlying implementation is > pluggable, > > you can use HBase, or any other KV store that supports timeline queries > or > > even a database(maybe for it's a small cluster). We provide model classes > > in jstorm-core, as to what kinds of metrics data need to be stored, it's > > totally up to the detailed implementation. Our internal implementation > uses > > OTS, which is a product of aliyun (https://www.aliyun.com/product/ots/), > > but it's easy to adapt to other implementations. > > > > On Fri, Mar 18, 2016 at 11:52 PM, Bobby Evans > <[email protected] > > > > > wrote: > > > > > Yes we originally wanted to try and use the Hadoop Timeline Server for > > > storm metrics feedback to nimbus + UI + history like server. But it > was > > > not stable at the time, so we stopped. For the sake of playing nicely > > with > > > the rest of the big data ecosystem I would like to see us support it as > > an > > > option for metrics collection/query, but until the timeline server v2 > is > > > ready and released. For me the important thing is that we have a > decent > > > time series DB that comes with storm by default and is pluggable so we > > can > > > replace it with something else that has similar capabilities in the > > future. > > > - Bobby > > > > > > On Friday, March 18, 2016 10:39 AM, Cody Innowhere < > > > [email protected]> wrote: > > > > > > > > > It's actually in Phase 2 of porting JStorm, but I'm absolutely ok to > > > discuss this in advance. > > > > > > On Fri, Mar 18, 2016 at 11:31 PM, Cody Innowhere <[email protected]> > > > wrote: > > > > > > > Yes it's already in production. > > > > The implementation basically follows the design document in > > > > https://issues.apache.org/jira/browse/STORM-1329, you can take a > look > > > > first and feel free to ask questions. > > > > > > > > On Fri, Mar 18, 2016 at 10:19 PM, Jungtaek Lim <[email protected]> > > > wrote: > > > > > > > >> Hi, > > > >> > > > >> I got something to do with metrics so I'm seeking the pull requests > > > which > > > >> addresses metrics. > > > >> And at #753 <https://github.com/apache/storm/pull/753> I found Cody > > > said > > > >> we > > > >> (maybe it means Alibaba team) are currently working on Metrics > Server. > > > >> (I also found comment which said there was some talk while ago > around > > > >> integrating Hadoop timeline server. Seems like no one came up with > the > > > >> result, and I prefer to avoid big dependency so I'm in favor of > > Metrics > > > >> Server for now.) > > > >> > > > >> I think that would improve metrics feature of Storm much better, so > > I'd > > > >> like to see how the work is going. Sure it's only when there's no > > issue > > > >> for > > > >> you to work transparently. I just would like to prevent duplication > of > > > >> work, and would like to help if needed and possible. > > > >> > > > >> Thanks, > > > >> Jungtaek Lim (HeartSaVioR) > > > >> > > > > > > > > > > > > > > > > > > > > > > >
