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Re: How many column families in one table ?
Thanks kevin

inder
"you are the average of 5 people you spend the most time with"
On Aug 4, 2013 8:35 PM, "Kevin O'dell" <[EMAIL PROTECTED]> wrote:

> Hi Inder,
>
>   Here is an excellent blog post which is a little dated:
>
> http://www.larsgeorge.com/2009/11/hbase-vs-bigtable-comparison.html?m=1
> On Aug 4, 2013 10:55 AM, "Inder Pall" <[EMAIL PROTECTED]> wrote:
>
> > Kevin
> >
> > Would love to hear your thoughts around hbase  not big table.
> >
> > Thanks
> >
> > inder
> > "you are the average of 5 people you spend the most time with"
> > On Aug 4, 2013 8:15 PM, "Kevin O'dell" <[EMAIL PROTECTED]> wrote:
> >
> > > Hi Vimal,
> > >
> > >   It really depends on your usage pattern but HBase != Bigtable.
> > > On Aug 4, 2013 2:29 AM, "Vimal Jain" <[EMAIL PROTECTED]> wrote:
> > >
> > > > Hi,
> > > > I have tested read performance after reducing number of column
> families
> > > > from 14 to 3 and yes there is improvement.
> > > > Meanwhile i was going through the paper published by google on
> > BigTable.
> > > > It says
> > > >
> > > > "It is our intent that the number of distinct column
> > > > families in a table be small (in the hundreds at most), and
> > > > that families rarely change during operation."
> > > >
> > > > So Is that theoretical value ( 100 CFs )  or its possible but not
> with
> > > the
> > > > current version of Hbase ?
> > > >
> > > >
> > > > On Tue, Jul 2, 2013 at 12:48 AM, Viral Bajaria <
> > [EMAIL PROTECTED]
> > > > >wrote:
> > > >
> > > > > On Mon, Jul 1, 2013 at 10:06 AM, Vimal Jain <[EMAIL PROTECTED]>
> > wrote:
> > > > >
> > > > > > Sorry for the typo .. please ignore previous mail.. Here is the
> > > > corrected
> > > > > > one..
> > > > > > 1)I have around 140 columns for each row , out of 140 , around
> 100
> > > > > columns
> > > > > > hold java primitive data type , remaining 40 columns  contain
> > > > serialized
> > > > > > java object as byte array(Inside each object is an ArrayList).
> Yes
> > ,
> > > I
> > > > do
> > > > > > delete data but the frequency is very less ( 1 out of 5K
> operations
> > > ).
> > > > I
> > > > > > dont run any compaction.
> > > > > >
> > > > >
> > > > > This answers the type of data in each cell not the size of data.
> Can
> > > you
> > > > > figure out the average size of data that you insert in that size.
> For
> > > > > example what is the length of the byte array ? Also for java
> > primitive,
> > > > is
> > > > > it 8-byte long ? 4-byte int ?
> > > > > In addition to that, what is in the row key ? How long is that in
> > > bytes ?
> > > > > Same for column family, can you share the names of the column
> family
> > ?
> > > > How
> > > > > about qualifiers ?
> > > > >
> > > > > If you have disabled major compactions, you should run it once a
> few
> > > days
> > > > > (if not once a day) to consolidate the # of files that each scan
> will
> > > > have
> > > > > to open.
> > > > >
> > > > > 2) I had ran scan keeping in mind the CPU,IO and other system
> related
> > > > > > parameters.I found them to be normal with system load being
> > 0.1-0.3.
> > > > > >
> > > > >
> > > > > How many disks do you have in your box ? Have you ever benchmarked
> > the
> > > > > hardware ?
> > > > >
> > > > > Thanks,
> > > > > Viral
> > > > >
> > > >
> > > >
> > > >
> > > > --
> > > > Thanks and Regards,
> > > > Vimal Jain
> > > >
> > >
> >
>