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HBase, mail # user - How many column families in one table ?


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Re: How many column families in one table ?
Viral Bajaria 2013-07-01, 19:18
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