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Date: Mon, 8 Nov 2010 14:01:50 -0600
Message-ID: <AANLkTi=eXsNjFTwsNu7b1y+VivGKE-y9uFTsC5X0ZBLE@mail.gmail.com>
Subject: Re: Design Question
From: Jonathan Ellis <jbellis@gmail.com>
To: user <user@cassandra.apache.org>
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Hi Mubarak,

Did you see David Strauss's talk on queing at the Summit?
http://riptano.blip.tv/file/4015190/

What specifics can you give as to how your use case is similar to /
different from what David covered?

On Sun, Nov 7, 2010 at 7:05 PM, Mubarak Seyed <mubarak.seyed@gmail.com> wro=
te:
> Hi All,
> Can someone please validate and recommend a solution for the given design
> problem?
> Problem statement: Need to de-queue data from Cassandra (from Standard
> ColumnFamily) using a job but multiple instances of a job can run
> simultaneously (kinda multiple threads), trying to access a same row but
> need to make sure that only one instance of a job (thread) can access a r=
ow,
> meaning if job A is accessing Row #1, then job B can't access Row #1.
> Possible solutions:
> Solution #1: Using Cages (and ZooKeeper) to make sure that one only job a=
t a
> time can access a row in CF. How do we make sure that Cages (transaction
> coordinator using ZooKeeper) is not a Single Point of Failure?=A0What is =
the
> performance impact on write/read on nodes?=A0There is some blog on distri=
buted
> concurrent queue
> at=A0http://www.cloudera.com/blog/2009/05/building-a-distributed-concurre=
nt-queue-with-apache-zookeeper/
> Solution #2: Using some home-grown approach to store/maintain who is
> accessing what, meaning which job is accessing which row.
> Are there any other solutions to the above problem?
> Can someone please help me on validate the design?
> --
> Thanks,
> Mubarak Seyed.
>


--=20
Jonathan Ellis
Project Chair, Apache Cassandra
co-founder of Riptano, the source for professional Cassandra support
http://riptano.com