hbase-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Nick Dimiduk <ndimi...@gmail.com>
Subject Re: performance of block cache
Date Thu, 21 Aug 2014 23:06:12 GMT
I'm familiar with Stack's work too, but thanks for pointing it out :)

On Wed, Aug 20, 2014 at 8:19 PM, 牛兆捷 <nzjemail@gmail.com> wrote:

> Hi Nick:
>
> Yes, I am interested in it. I will try first.
>
> Btw, this site (http://people.apache.org/~stack/bc/) also does the similar
> performance evaluation.
> You can have a look if you are interested in.
>
>
> 2014-08-21 1:48 GMT+08:00 Nick Dimiduk <ndimiduk@gmail.com>:
>
> > Hi Zhaojie,
> >
> > I'm responsible for this particular bit of work. One thing to note in
> these
> > experiments is that I did not control explicitly for OS caching. I ran
> > "warmup" workloads before collecting measurements, but because the amount
> > of RAM on the machine is fixed, it's impact of OS cache is different with
> > different based on the amount of memory used by HBase. Another, as Todd
> > pointed out on an earlier thread, is that my trend lines are probably
> > optimistic/misleading.
> >
> > Something I was driving for was to understand how well the different
> > implementations before as they're managing more and more memory. I'd like
> > to get some insight into how we might be able to take advantage of 100's
> or
> > even 1000's of GB of memory when the time comes. That's part of why
> there's
> > so many variables.
> >
> > I scripted out the running of the tests, all of my configurations are
> > available in the associated github repo [0], and all of the data points
> are
> > available as a csv. If you're interested in experimenting yourself,
> please
> > let me know how I can help.
> >
> > Cheers,
> > Nick
> >
> > [0]: https://github.com/ndimiduk/perf_blockcache
> >
> >
> > On Wed, Aug 20, 2014 at 6:00 AM, 牛兆捷 <nzjemail@gmail.com> wrote:
> >
> > > the complete blog link is:
> > > http://zh.hortonworks.com/blog/blockcache-showdown-hbase/
> > >
> > >
> > > 2014-08-20 11:41 GMT+08:00 牛兆捷 <nzjemail@gmail.com>:
> > >
> > > > Hi all:
> > > >
> > > > I saw some interesting results from Hortonworks blog (block cache
> > > > <
> > >
> >
> http://zh.hortonworks.com/wp-content/uploads/2014/03/perfeval_blockcache_v2.pdf
> > > >
> > > > ).
> > > >
> > > > In this result, the ratio of memory footprint to database size is
> held
> > > > fixed while
> > > > the absolute values are increased.
> > > >
> > > > In my mind, the performance should becomes worse for larger ratio as
> > the
> > > > increase
> > > > of the absolute value. For example BucketCache#(tmpfs), the
> difference
> > > > between ratio (DB"1.5":"RAM"1.0) and ratio (DB"4.5":"RAM"1.0) becomes
> > > > larger as the increase of memory.
> > > > Actually, the result of ratio ( DB"1.5":"RAM"1.0) increase linearly,
> > and
> > > > the result of ratio (DB"1.5":"RAM"1.0) exponentially.
> > > >
> > > > However, for BucketCache#(heap) and LruBlockCache, the result is out
> of
> > > my
> > > > expectation.
> > > > The curves of ratio (DB"1.5":"RAM"1.0) and ratio (DB"4.5":"RAM"1.0)
> > both
> > > > increase exponentially, but the relative differences as the increase
> of
> > > > memory are not consistent.
> > > > Take LruBlockCache as an example, the difference of ratio
> > > > (DB"1.5":"RAM"1.0) and ratio (DB"4.5":"RAM"1.0) becomes smaller from
> 20
> > > GB
> > > > to 50 GB, but becomes larger from 50 GB to 60 GB.
> > > >
> > > > How to analysis the cause of this result, any ideas?
> > > >
> > > > --
> > > > *Regards,*
> > > > *Zhaojie*
> > > >
> > > >
> > >
> > >
> > > --
> > > *Regards,*
> > > *Zhaojie*
> > >
> >
>
>
>
> --
> *Regards,*
> *Zhaojie*
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message