Hi Jonathan,
Thank you for the timely reply. I am doing this experiment on a continuous basis. To be more specific, I will issue a large amount of read and write operations to a particular key in a short time interval. I'd like to know the order that write operations happens at each replica. TImestamps definitely help to determine order, but the WRITETIME and SStable2Json both looks me only return the timestamps when that key was updated the moment the WRITETIME/SStable2Json is issued. It looks like a one time thing to me. Or put in another way, if I want to get the write time for all write operations in that short invertal to determine a total order for write on that replia I have to constantly issue WRITETIME to this replica? Correct me if I am wrong here. Light me up pleeeeeeeeeease! On Tue, 18 Mar 2014 15:05:07 -0400, Jonathan Lacefield wrote: > Hello, > Is this a one time investigative item or are you looking to set something up to do this continuously? Don't recommend trying to read the commit log. > You can always use the WRITETIME function in CQL or look within SSTables via the SStable2Json utility to see write times for particular versions of partitions. > Jonathan > > Jonathan Lacefield > Solutions Architect, DataStax > (404) 822 3487 > [1] > [2] > > On Tue, Mar 18, 2014 at 2:25 PM, Han,Meng wrote: > >> Hi Cassandra hackers! >> >> I have a question regarding extracting useful information from commit log. >> >> Since its a binary log, how should I extract information such as timestamp, values from it? Does anyone know any binary log reader that I can use directly to read commit log? >> If there is no such reader, could someone give me some advice hwo I can wrote such a reader? >> >> Particularly, I want to know the order that write operations happens at each replica(cassandra server node) along with their timestamps, Does anyone know other methods how I can get this information without instrumenting Cassandra code? >> >> Any help is appreciated! >> >> Cheers, >> Meng Links: ------ [1] http://www.linkedin.com/in/jlacefield [2] http://www.datastax.com/what-we-offer/products-services/training/virtual-training [3] mailto:meng...@ufl.edu
