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HBase >> mail # user >> Write TimeSeries Data and Do Time Based Range Scans


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Re: Write TimeSeries Data and Do Time Based Range Scans
Yeah, I saw that. In fact that is why I recommended that to you as I
couldn't infer from your email that whether you have already gone through
that source or not. A source, who did the exact same thing and discuss it
in much more detail and concerns aligning with yours (in fact I think some
of the authors/creators of that link/group are members here of this
community as well.)

Regards,
Shahab
On Mon, Sep 23, 2013 at 8:41 PM, anil gupta <[EMAIL PROTECTED]> wrote:

> Hi Shahab,
>
> If you read my solution carefully. I am already doing that.
>
> Thanks,
> Anil Gupta
>
>
> On Mon, Sep 23, 2013 at 3:51 PM, Shahab Yunus <[EMAIL PROTECTED]
> >wrote:
>
> >
> >
> http://blog.sematext.com/2012/04/09/hbasewd-avoid-regionserver-hotspotting-despite-writing-records-with-sequential-keys/
> >
> > Here you can find the discussion, trade-offs and working code/API (even
> for
> > M/R) about this and the approach you are trying out.
> >
> > Regards,
> > Shahab
> >
> >
> > On Mon, Sep 23, 2013 at 5:41 PM, anil gupta <[EMAIL PROTECTED]>
> wrote:
> >
> > > Hi All,
> > >
> > > I have a secondary index(inverted index) table with a rowkey on the
> basis
> > > of Timestamp of an event. Assume the rowkey as <TimeStamp in Epoch>.
> > > I also store some extra(apart from main_table rowkey) columns in that
> > table
> > > for doing filtering.
> > >
> > > The requirement is to do range-based scan on the basis of time of
> > > event.  Hence, the index with this rowkey.
> > > I cannot use Hashing or MD5 digest solution because then i cannot do
> > range
> > > based scans.  And, i already have a index like OpenTSDB in another
> table
> > > for the same dataset.(I have many secondary Index for same data set.)
> > >
> > > Problem: When we increase the write workload during stress test. Time
> > > secondary index becomes a bottleneck due to the famous Region
> HotSpotting
> > > problem.
> > > Solution: I am thinking of adding a prefix of { (<TimeStamp in
> > Epoch>%10) > > > bucket}  in the rowkey. Then my row key will become:
> > >  <Bucket><TimeStamp in Epoch>
> > > By using above rowkey i can at least alleviate *WRITE* problem.(i don't
> > > think problem can be fixed permanently because of the use case
> > requirement.
> > > I would love to be proven wrong.)
> > > However, with the above row key, now when i want to *READ* data, for
> > every
> > > single range scans i have to read data from 10 different regions. This
> > > extra load for read is scaring me a bit.
> > >
> > > I am wondering if anyone has better suggestion/approach to solve this
> > > problem given the constraints i have.  Looking for feedback from
> > community.
> > >
> > > --
> > > Thanks & Regards,
> > > Anil Gupta
> > >
> >
>
>
>
> --
> Thanks & Regards,
> Anil Gupta
>