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From Anoop John <anoop.hb...@gmail.com>
Subject Re: HBase and Accumulo
Date Thu, 20 Aug 2015 17:24:38 GMT
>>4) HBase's Cell Level Visiblity Expression needs some scale-tests to
figure
>>out the exact boundary, but it will probably have  bad time at ~millions
or
>>~10s of millions of unique labels.

>>Most use cases won't be impacted by this, I expect.

 >>5) HBase stores a representation of the visibility expression rather than
>>the raw expression with each cell.


I know Sean you are telling abt 1.1.1 version.  In trunk we do have ways
with which we can store the raw vis expression with cells rather than the
ordinal based representation.  By default it will be ordinal based bit
position ON or OFF mechanism.  This is done because at the scan time, the
expression matching will be much faster as we dont have to evaluate the raw
expression and then do string matching. When the total set of labels is not
so big , this model will be much better.  Agree that will have an issue
when millions of labels. Different reasons for that. As other system
tables, labels table also single region.  We use zk based notification bus
to sync RSs for labels.  The 2nd one will get solved once we rewrite it to
use proc V2 based solution.
So for such usages of huge #labels, we can go with raw expression storing
way.


-Anoop-


On Thu, Aug 20, 2015 at 6:35 AM, Jerry He <jerryjch@gmail.com> wrote:

> I definitely agree HBase has a broader base.  Thanks, Ted.
>
> Jerry
>
> On Wed, Aug 19, 2015 at 4:42 PM, Ted Malaska <ted.malaska@cloudera.com>
> wrote:
>
> > I would say most banks are hbase but there r a few with accumulo.  I have
> > most bank, broker dealers and regulators in my region. Also I think we r
> > talking about the same foreign bank ;)
> >
> > Ted Malaska
> > On Aug 19, 2015 7:15 PM, "Jerry He" <jerryjch@gmail.com> wrote:
> >
> > > Hi, folks
> > >
> > > Thanks so much for all the responses and comments.
> > >
> > > We don't have or support Accumulo yet  We support HBase.  There have
> been
> > > requests for Accumulo. Like Ted said, almost all from Federal sector
> and
> > > Banks (even foreign banks).
> > > They seem to have References or reference implementations for their use
> > > cases.  My work of persuasion for HBase has not been very successful.
> > >
> > > I had looked into the HBase cell security. There are maybe some
> > differences
> > > and misses like Sean mentioned. I think overall the visibility coverage
> > > plus the ACL are great.
> > >
> > > Technology aside, Accumulo's reputation in the specific areas it is
> good
> > at
> > > is probably there.
> > >
> > > It will probably be slow evolving process ...
> > >
> > > Jerry
> > >
> > >
> > >
> > > On Wed, Aug 19, 2015 at 3:54 PM, Ted Malaska <ted.malaska@cloudera.com
> >
> > > wrote:
> > >
> > > > I'm on the side of benchmarking for the use case and with an expert.
> > > There
> > > > a so many ways to cheat a benchmark.  And the bench mark may not be
> > > > anything like your use case.
> > > > On Aug 19, 2015 5:43 PM, "Andrew Purtell" <apurtell@apache.org>
> wrote:
> > > >
> > > > > I think someone who uses third party benchmarks to assess a system
> > like
> > > > > HBase or Accumulo (or Cassandra...) is taking a foolish shortcut,
> so
> > > > > perhaps we must agree to disagree.
> > > > >
> > > > >
> > > > > On Wed, Aug 19, 2015 at 2:34 PM, Jeremy Kepner <kepner@ll.mit.edu>
> > > > wrote:
> > > > >
> > > > > > I agree, that performance on real apps is the most important
for
> > > > > > any particular organization, but as technologists how do we
> measure
> > > > > > ourselves?
> > > > > > Hence imperfect benchmarking remains our only recourse.
> > > > > >
> > > > > > On Wed, Aug 19, 2015 at 12:34:44PM -0700, Andrew Purtell wrote:
> > > > > > > I can't speak for anyone other than myself in the HBase
> > community,
> > > > but
> > > > > > I'm
> > > > > > > much more interested and focused on performance analysis
and
> > > > > > > developing/deploying for the use cases of my employer than
> > > > > participating
> > > > > > in
> > > > > > > generic bench-marketing to make weapons for happy OSS warriors.
> > > > Perhaps
> > > > > > > this does a disservice to the HBase project overall and
if so
> > then
> > > I
> > > > > > > apologize to others on the project for that.
> > > > > > >
> > > > > > > That said, from long and bitter experience let me state
the
> only
> > > > > > benchmarks
> > > > > > > that every really matter are the comparative benchmarks
you
> make
> > > for
> > > > > your
> > > > > > > own use cases in your own environments, preferably exercising
> > those
> > > > > > > candidates with real data and operating conditions. See:
> > > > > > > https://pbs.twimg.com/media/CMnTyKVUEAA1tOm.jpg (smile)
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > > > On Wed, Aug 19, 2015 at 12:27 PM, Josh Elser <
> > josh.elser@gmail.com
> > > >
> > > > > > wrote:
> > > > > > >
> > > > > > > > Alright, I have to ask... are you referring to the
paper that
> > > cites
> > > > > > > > Accumulo performance without write-ahead logs enabled?
I have
> > > some
> > > > > > serious
> > > > > > > > reservations about the relevance of that paper to
this
> > > conversation
> > > > > and
> > > > > > > > just want to make sure people aren't led astray by
what the
> > > actual
> > > > > > takeaway
> > > > > > > > should be.
> > > > > > > >
> > > > > > > > Jeremy Kepner wrote:
> > > > > > > >
> > > > > > > >> A big difference between Accumulo and HBase is
the published
> > > > > > performance
> > > > > > > >> numbers.
> > > > > > > >> The Accumulo community has done a good job of
continuing to
> > > > publish
> > > > > > > >> up-to-date performance
> > > > > > > >> numbers in peer-reviewed venues which allow Accumulo
to
> claim
> > > best
> > > > > in
> > > > > > the
> > > > > > > >> world performance.
> > > > > > > >>
> > > > > > > >> The HBase community hasn't been doing that so
much.  It
> would
> > be
> > > > > > great if
> > > > > > > >> they did because
> > > > > > > >> the HBase points on the graphs are old and it
would be good
> to
> > > get
> > > > > new
> > > > > > > >> ones.
> > > > > > > >>
> > > > > > > >>
> > > > > > > >>
> > > > > > > >> On Wed, Aug 19, 2015 at 02:30:58PM -0400, Josh
Elser wrote:
> > > > > > > >>
> > > > > > > >>> Like I've said many times now, it's relative
to your actual
> > > > > problem.
> > > > > > > >>> If you don't have that much data (or intend
to grow into
> that
> > > > much
> > > > > > > >>> data), it's not an issue. Obviously, this
is the case for
> > you.
> > > > > > > >>>
> > > > > > > >>> However, it is an architectural difference
between the two
> > > > projects
> > > > > > > >>> with known limitations for a single metadata
region. It's a
> > > > > > > >>> difference as what was asked for by Jerry.
> > > > > > > >>>
> > > > > > > >>> Ted Malaska wrote:
> > > > > > > >>>
> > > > > > > >>>> I've been doing HBase for a long time
and never had an
> issue
> > > > with
> > > > > > region
> > > > > > > >>>> count limits and I have clusters with
10s of billions of
> > > > records.
> > > > > > Many
> > > > > > > >>>> there would be issues around a couple
Trillion records,
> but
> > > > never
> > > > > > got
> > > > > > > >>>> that
> > > > > > > >>>> high yet.
> > > > > > > >>>>
> > > > > > > >>>> Ted Malaska
> > > > > > > >>>>
> > > > > > > >>>> On Wed, Aug 19, 2015 at 2:24 PM, Josh
Elser<
> > > > josh.elser@gmail.com>
> > > > > > > >>>>  wrote:
> > > > > > > >>>>
> > > > > > > >>>> Oh, one other thing that I should mention
(was prompted
> > > > off-list).
> > > > > > > >>>>>
> > > > > > > >>>>> (definition time since cross-list
now: HBase regions ==
> > > > Accumulo
> > > > > > > >>>>> tablets)
> > > > > > > >>>>>
> > > > > > > >>>>> Accumulo will handle many more regions
than HBase does
> now
> > > due
> > > > > to a
> > > > > > > >>>>> splittable metadata table. While I
was told this was a
> very
> > > > long
> > > > > > and
> > > > > > > >>>>> arduous journey to implement correctly
(WRT splitting,
> > merges
> > > > and
> > > > > > bulk
> > > > > > > >>>>> loading), users with "too many regions"
problems are
> > > extremely
> > > > > few
> > > > > > and
> > > > > > > >>>>> far
> > > > > > > >>>>> between for Accumulo.
> > > > > > > >>>>>
> > > > > > > >>>>> I was very happy to see effort/design
being put into this
> > in
> > > > > HBase.
> > > > > > > >>>>> And,
> > > > > > > >>>>> just to be fair in criticism/praises,
HBase does appear
> to
> > me
> > > > to
> > > > > do
> > > > > > > >>>>> assignments of regions much faster
than Accumulo does on
> a
> > > > small
> > > > > > > >>>>> cluster
> > > > > > > >>>>> (~5-10 nodes). Accumulo may take a
few seconds to notice
> > and
> > > > > > reassign
> > > > > > > >>>>> tablets. I have yet to notice this
with HBase (which also
> > > could
> > > > > be
> > > > > > due
> > > > > > > >>>>> to
> > > > > > > >>>>> lack of personal testing).
> > > > > > > >>>>>
> > > > > > > >>>>>
> > > > > > > >>>>> Jerry He wrote:
> > > > > > > >>>>>
> > > > > > > >>>>> Hi, folks
> > > > > > > >>>>>>
> > > > > > > >>>>>> We have people that are evaluating
HBase vs Accumulo.
> > > > > > > >>>>>> Security is an important factor.
> > > > > > > >>>>>>
> > > > > > > >>>>>> But I think after the Cell security
was added in HBase,
> > > there
> > > > is
> > > > > > no
> > > > > > > >>>>>> more
> > > > > > > >>>>>> real gap compared to Accumulo.
> > > > > > > >>>>>>
> > > > > > > >>>>>> I know we have both HBase and
Accumulo experts on this
> > list.
> > > > > > > >>>>>> Could someone shred more light?
> > > > > > > >>>>>> I am looking for real gap comparing
HBase to Accumulo if
> > > there
> > > > > is
> > > > > > any
> > > > > > > >>>>>> so
> > > > > > > >>>>>> that I can be prepared to address
them. This is not
> > limited
> > > to
> > > > > the
> > > > > > > >>>>>> security
> > > > > > > >>>>>> area.
> > > > > > > >>>>>>
> > > > > > > >>>>>> There are differences in some
features and
> > implementations.
> > > > But
> > > > > > they
> > > > > > > >>>>>> don't
> > > > > > > >>>>>> see like real 'gaps'.
> > > > > > > >>>>>>
> > > > > > > >>>>>> Any comments and feedbacks are
welcome.
> > > > > > > >>>>>>
> > > > > > > >>>>>> Thanks,
> > > > > > > >>>>>>
> > > > > > > >>>>>> Jerry
> > > > > > > >>>>>>
> > > > > > > >>>>>>
> > > > > > > >>>>>>
> > > > > > >
> > > > > > >
> > > > > > > --
> > > > > > > Best regards,
> > > > > > >
> > > > > > >    - Andy
> > > > > > >
> > > > > > > Problems worthy of attack prove their worth by hitting
back. -
> > Piet
> > > > > Hein
> > > > > > > (via Tom White)
> > > > > >
> > > > >
> > > > >
> > > > >
> > > > > --
> > > > > Best regards,
> > > > >
> > > > >    - Andy
> > > > >
> > > > > Problems worthy of attack prove their worth by hitting back. - Piet
> > > Hein
> > > > > (via Tom White)
> > > > >
> > > >
> > >
> >
>

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