AFAIR raid10 should be around 2x faster on both read and write operations 
comparing to a simple jbod.

Sent from my iPad

On 2010-09-26, at 10:09 PM, Tao Xie <[email protected]> wrote:

> Thanks, Ryan. But in the paper they said their Read operations retrieves an
> entire record. And my nodes get even more memory than theirs. They has only
> 8GB ram while I got 24GB. The only difference is I use JBOD rather than
> RAID10 array. I think JBOD would be better for HDFS than RAID. Is that
> right?
> 
> 
> 2010/9/27 Ryan Rawson <[email protected]>
> 
>> hey,
>> 
>> there are a lot of settings which all affect speed, you might want to
>> make sure you are running the exact config the paper is. for example
>> "readallfields".. if you have a wide column setting it to 'true' will
>> go much slower (since you are returning a lot more data) than if you
>> set it to false.  Also there are known bottlenecks in our HTable
>> client, which exist to reduce the # of socket connections, but you can
>> get higher performance with multiple VMs, although that is more
>> complex.
>> 
>> Also dont forget hardware.. .make sure your HW is the same as the papers.
>> 
>> Good luck!
>> -ryan
>> 
>> On Sat, Sep 25, 2010 at 8:19 AM, Tao Xie <[email protected]> wrote:
>>> I want to reproduce the results in the ycsb paper. I  run hbase 0.20.6
>> and
>>> hadoop 0.20.2. My cluster is like this:
>>> 
>>> 1 Node as HMaster + ZK
>>> 
>>> 6 Nodes as DN, RS
>>> 
>>> 1 Node as Hbase client.
>>> 
>>> I think this environment is something like the one used by the paper.
>>> 
>>> When I run tests like workloadb with 100 threads, I get at most 2500
>> ops/sec
>>> throughput and read latency is about 40~50 ms, which is much higher than
>> the
>>> paper results (about 10+ ms). I wonder if anybody is running ycsb too and
>>> can give me some hints.
>>> 
>>> 
>>> 
>>> Thanks in advance.
>>> 
>> 

Reply via email to