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Re: write throughput in cassandra, understanding hbase
Hi S Ahmed,

  How are you today?  I wanted to echo what Lars said Most of these tests
have an agenda.  With that being said, have you done an of your own
internal testing?  If so do you have configs, row keys, or results that you
can share with us so that we can help you tune your cluster for success?

On Tue, Jan 22, 2013 at 2:03 PM, lars hofhansl <[EMAIL PROTECTED]> wrote:

> Where do you see that HBase is doing only 2-3k writes/s?
> How was the data distributed? Was the table split?
> Cassandra uses a random partitioner by default, which will nicely
> distribute the data over the cluster but won't allow to perform range scans
> over your data.
> HBase always partitions by key ranges, so that the keys can the range
> scanned. If that is not done correctly and you create monotonically
> increasing keys, you'll hotspot a single region server.
>
> Even then, you can do more than this on single RegionServer.
>
> Also note that many of the benchmarks have agendas and cherry pick the
> results.
> They probably "forgot" to disabled Nagle's and to distribute the table
> correctly.
>
> -- Lars
>
>
>
> ________________________________
>  From: S Ahmed <[EMAIL PROTECTED]>
> To: [EMAIL PROTECTED]
> Sent: Tuesday, January 22, 2013 10:38 AM
> Subject: RE: write throughput in cassandra, understanding hbase
>
> I've read articles online where I see cassandra doing like 20K writers per
> second, and hbase around 2-3K.
>
> I understand both systems have their strenghts, but I am curious as to what
> is holding hbase from reaching similiar results?
>
> Is it HDFS that is the issue?  Or hbase does certain things (to its
> advantage) that slows the write path down?
>

--
Kevin O'Dell
Customer Operations Engineer, Cloudera