On Fri, May 13, 2011 at 10:57 PM, Jean-Daniel Cryans <[email protected]>wrote:

> It says:
>
> "The master and namenode are the entry points of
> their respective levels, meaning that if an HBase client wants
> a specific data, it first has to ask to the master that knows
> which is the region server that stores it."
>
> Which is wrong, quoting the Bigtable paper (which your team should
> consider reading):
>

Yes I know, this is exactly what tsuna previously pointed out. This error is
now corrected.


>
> "As with many single-master distributed storage sys-
> tems [17, 21], client data does not move through the mas-
> ter: clients communicate directly with tablet servers for
> reads and writes. Because Bigtable clients do not rely on
> the master for tablet location information, most clients
> never communicate with the master. As a result, the mas-
> ter is lightly loaded in practice."
>
> Which also impacts your conclusion:
>
> "For example it can be interesting to
> see when a system based on an architecture using a single
> point of entry, such as HBase and its master, would be overload"
>
>
Indeed, I'm going to change that as well.


> J-D
>
> On Fri, May 13, 2011 at 4:06 AM, Thibault Dory <[email protected]>
> wrote:
> > Hello,
> >
> > I have written with a few other people a paper for the ACM Symposium
> > On Cloud Computing. This paper describes the methodology,
> > infrastructure and configuration used as well as the results obtained
> > for elasticity and scalability of three noSQL databases, of wich
> > HBase. The paper can be downloaded here :
> > http://www.nosqlbenchmarking.com/wp-content/uploads/2011/05/paper.pdf<
> http://www.google.com/url?sa=D&q=http://www.nosqlbenchmarking.com/wp-content/uploads/2011/05/paper.pdf
> >
> >
> >
> > Any feedback on the methodology used would be appreciated, we would
> > like to know if HBase is used in a "fair" way in those tests.
> >
> > We also encountered a problem with the distribution of requests among
> region
> > servers. This problem is described in section 5.4.2 and any hints on how
> to
> > solve this problem would be appreciated. Please note that the request
> > generation is independent of the specific database layer and that we did
> not
> > observe this problem for the two other databases.
> >
> > Regards,
> >
> > Thibault Dory
> >
>

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