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Re: 答复: some ideas for QJM and NFS
All JNs are deployed on the same node with DN.
On Mon, Feb 18, 2013 at 3:35 PM, 谢良 <[EMAIL PROTECTED]> wrote:

>  Hi Azuryy, just want to confirm one thing, your JN did not deploy on the
> same machines within DN, right ?
>
> Regards,
> Liang
>   ------------------------------
> *发件人:* Azuryy Yu [[EMAIL PROTECTED]]
> *发送时间:* 2013年2月18日 15:22
> *收件人:* [EMAIL PROTECTED]
> *主题:* Re: some ideas for QJM and NFS
>
>   Hi,
>
> I did it on hadoop-2.0.3-alpha without HA as following:
>
> [root@webdm test]# date +%Y-%m-%d_%H:%M:%S; hdfs dfs -put
> testspeed.tar.gz / ; date +%Y-%m-%d_%H:%M:%S
> 2013-02-18_15:20:01
> 13/02/18 15:20:02 WARN util.NativeCodeLoader: Unable to load native-hadoop
> library for your platform... using builtin-java classes where applicable
> 2013-02-18_15:20:30
>
>  so the performance is a little bit better than hadoop-1.0.4.
>
>
>
> On Mon, Feb 18, 2013 at 2:53 PM, Azuryy Yu <[EMAIL PROTECTED]> wrote:
>
>> Oh, yes, you are right, George. I'll probably do it in the next days.
>>
>>
>> On Mon, Feb 18, 2013 at 2:47 PM, George Datskos <
>> [EMAIL PROTECTED]> wrote:
>>
>>>  Hi Azuryy,
>>>
>>> So you have measurements for hadoop-1.0.4 and hadoop-2.0.3+QJM, but I
>>> think you should also measure hadoop-2.0.3 _wihout_ QJM so you can know for
>>> sure if the performance degrade is actually related to QJM or not.
>>>
>>>
>>> George
>>>
>>>
>>>    Hi,
>>>
>>>  HarshJ is a good guy, I've seen this JIRA:
>>> https://issues.apache.org/jira/browse/HDFS-4508
>>>
>>>  I have a test cluster hadoop-1.0.4, I've upgrade to
>>> hadoop-2.0.3-alpha. mu cluster is very small, four nodes totally.
>>>
>>>  then I did some test on the original Hadoop and new Hadoop, the
>>> testing is very simple: I have a data file with 450MB, I just put it on the
>>> HDFS.
>>>
>>>  block size: 128MB, replica: 2
>>>
>>>  the following is the result:
>>>
>>> [root@webdm test]# ll testspeed.tar.gz
>>> -rw-r--r-- 1 root root 452M Feb 18 13:54 testspeed.tar.gz
>>> [root@webdm test]#
>>>
>>>  //On the hadoop-1.0.4
>>>  [root@webdm test]# date +%Y-%m-%d_%H:%M:%S; hadoop dfs -put
>>> testspeed.tar.gz / ; date +%Y-%m-%d_%H:%M:%S
>>> 2013-02-18_13:54:24
>>> Warning: $HADOOP_HOME is deprecated.
>>> 2013-02-18_13:54:58
>>>
>>>  //On the hadoop-2.0.3-alpha with QJM
>>>  [root@webdm test]# date +%Y-%m-%d_%H:%M:%S; hdfs dfs -put
>>> testspeed.tar.gz / ; date +%Y-%m-%d_%H:%M:%S
>>> 2013-02-18_14:13:29
>>> 13/02/18 14:13:30 WARN util.NativeCodeLoader: Unable to load
>>> native-hadoop library for your platform... using builtin-java classes where
>>> applicable
>>> 2013-02-18_14:14:33
>>>
>>>  I do think QJM HA feature affect the performance, because each writer
>>> from QJM, it will do: fence old writer; sync in-progress log; start new log
>>> segment; then write. only if writer received a successful response from a
>>> quorum of JNs, writer finished for this time.
>>>
>>>  But NFS HA just write log segment in the local and NFS, when it
>>> receive successful response from NFS, it finished this time.
>>>
>>>  So, I just suggest we always keep these two HA features in future,
>>> even in the stable release. which one should be used, which depends on
>>> yourself based on your infrastructure.
>>>
>>>  Thanks.
>>>
>>>
>>>
>>
>