Let me try to reproduce your test and get back wiith some results. Regards,
Carlos Juzarte Rolo Cassandra Consultant Pythian - Love your data rolo@pythian | Twitter: cjrolo | Linkedin: *linkedin.com/in/carlosjuzarterolo <http://linkedin.com/in/carlosjuzarterolo>* Mobile: +31 6 159 61 814 | Tel: +1 613 565 8696 x1649 www.pythian.com On Fri, Apr 24, 2015 at 2:35 AM, Bongseo Jang <grayce...@gmail.com> wrote: > Thanks a lot Carlos, Sebastian :-) > > My test was with 1 node/1 replica settings, on which I assumed client > request = read request on the graph. Because there seems no read_repair and > already CL=ONE in my case, I need more explanation, don't I? Or can any > other internals be still involved? > > Do you have more suggestions? I want to design new test narrowing the gap > on the suggestions. > > On 24 April 2015 at 00:23, Sebastian Estevez < > sebastian.este...@datastax.com> wrote: > >> Carlos is right: >> >> *Read Requests* - The number of read requests per second on the >> coordinator nodes, analogous to client reads. Monitoring the number of >> requests over a given time period reveals system read workload and usage >> patterns. >> >> *Avg* - The average of values recorded during a time interval. >> >> A future version of OpsC will include tooltips with these descriptions >> for better clarity. >> On Apr 23, 2015 6:30 AM, "Carlos Rolo" <r...@pythian.com> wrote: >> >>> Probably it takes in account the read repair, plus a read that have >>> consistency != 1 will produce reads on other machines (which are taken in >>> account). I don't know the internals of opscenter but I would assume that >>> this is the case. >>> >>> If you want to test it further, disable read_repair, and make all your >>> reads with CL=ONE. Then your client and Opscenter should match. >>> >>> PS: Speculative_retry could also send reads over to more machines. >>> >>> Regards, >>> >>> Carlos Juzarte Rolo >>> Cassandra Consultant >>> >>> Pythian - Love your data >>> >>> rolo@pythian | Twitter: cjrolo | Linkedin: >>> *linkedin.com/in/carlosjuzarterolo >>> <http://linkedin.com/in/carlosjuzarterolo>* >>> Mobile: +31 6 159 61 814 | Tel: +1 613 565 8696 x1649 >>> www.pythian.com >>> >>> On Thu, Apr 23, 2015 at 10:34 AM, Bongseo Jang <grayce...@gmail.com> >>> wrote: >>> >>>> I have cassandra 2.1 + OpsCenter 5.1.1 and test them. >>>> >>>> When I monitored with opscenter 'read requests' graph, it seems the >>>> number on the graph is not what I expected, the number of client requests >>>> or responses. >>>> >>>> I recorded actual number of client request and compare it with graph, >>>> then found they're different. The number on the graph is about 4 times >>>> larger than what the client claimed. >>>> >>>> So, my question is what 'Read Reuqests' on OpsCenter counts exaclty ? >>>> >>>> Thanks ! >>>> >>>> -- >>>> Regards, >>>> Jang. >>>> >>>> a sound mind in a sound body >>>> >>> >>> >>> -- >>> >>> >>> >>> > > > -- > Regards, > Jang. > > a sound mind in a sound body > -- --
