Hi Yehia,

Oh? I thought that by using maxResources = 15360 mb (3072 mb * 5), vcores = 5, 
and maxMaps = 5, I already restricting the job to only use 5 maps at max.

The reason is my long run job have 841 maps, and each map will process data for 
almost 2 hours.
In the meantime there will be some short jobs that only need couple of minutes 
to complete.
Hence why I use fair scheduler to split resources into 2 groups, one default 
and other one longrun.
I want to make sure there always an available resources ready to be used by 
short jobs.

If your explanation is true, then current fair scheduler behavior is not what I 
wanted.
So is there any other ways to setup YARN resources to accommodate the short / 
long run jobs?
Or do I need to create 2 separate YARN cluster? (I have been thinking about 
this approach)

Best regards,
Henry

From: Yehia Elshater [mailto:[email protected]]
Sent: Wednesday, August 13, 2014 11:27 AM
To: [email protected]
Subject: Re: fair scheduler not working as intended

Hi Henry,

Are there any applications (on different queues rather than longrun queue) are 
running in the same time ? I think FairScheduler is going to assign more 
resources to your "longrun" as long as there no other applications are running 
in the other queues.

Thanks
Yehia

On 12 August 2014 20:30, Henry Hung 
<[email protected]<mailto:[email protected]>> wrote:
Hi Everyone,

I’m using Hadoop-2.2.0 with fair scheduler in my YARN cluster, but something is 
wrong with the fair scheduler.

Here is my fair-scheduler.xml looks like:

<allocations>
  <queue name="longrun">
    <maxResources>15360 mb, 5 vcores</maxResources>
    <weight>0.5</weight>
    <minMaps>2</minMaps>
    <maxMaps>5</maxMaps>
    <minReduces>1</minReduces>
  </queue>
</allocations>

I create a “longrun” queue to ensure that huge MR application can only use 5 
resources. My YARN setup for each resource memory is 3072 MB:

  <property>
    <name>mapreduce.map.memory.mb</name>
    <value>3072</value>
  </property>
  <property>
    <name>mapreduce.reduce.memory.mb</name>
    <value>3072</value>
  </property>

When the huge application started, it works just fine and scheduler restrict it 
to only run 5 maps in parallel.
But after running for some time, the application run 10 maps in parallel.
The scheduler page show that the “longrun” queue used 66%, exceed the fair 
share 30%.

Can anyone tell me why the application can get more than it deserved?
Is the problem with my configuration? Or there is a bug?

Best regards,
Henry Hung

________________________________
The privileged confidential information contained in this email is intended for 
use only by the addressees as indicated by the original sender of this email. 
If you are not the addressee indicated in this email or are not responsible for 
delivery of the email to such a person, please kindly reply to the sender 
indicating this fact and delete all copies of it from your computer and network 
server immediately. Your cooperation is highly appreciated. It is advised that 
any unauthorized use of confidential information of Winbond is strictly 
prohibited; and any information in this email irrelevant to the official 
business of Winbond shall be deemed as neither given nor endorsed by Winbond.


________________________________
The privileged confidential information contained in this email is intended for 
use only by the addressees as indicated by the original sender of this email. 
If you are not the addressee indicated in this email or are not responsible for 
delivery of the email to such a person, please kindly reply to the sender 
indicating this fact and delete all copies of it from your computer and network 
server immediately. Your cooperation is highly appreciated. It is advised that 
any unauthorized use of confidential information of Winbond is strictly 
prohibited; and any information in this email irrelevant to the official 
business of Winbond shall be deemed as neither given nor endorsed by Winbond.

Reply via email to