hmmmm…  

my observation is that, master in Spark 1.1 has higher frequency of GC……

Also, before 1.1, I never encounter GC overtime in Master, after upgrade to 
1.1, I have met for 2 times (we upgrade soon after 1.1 release)….

Best,  

--  
Nan Zhu


On Thursday, October 23, 2014 at 1:08 PM, Andrew Or wrote:

> Yeah, as Sameer commented, there is unfortunately not an equivalent 
> `SPARK_MASTER_MEMORY` that you can set. You can work around this by starting 
> the master and the slaves separately with different settings of 
> SPARK_DAEMON_MEMORY each time.
>  
> AFAIK there haven't been any major changes in the standalone master in 1.1.0, 
> so I don't see an immediate explanation for what you're observing. In general 
> the Spark master doesn't use that much memory, and even if there are many 
> applications it will discard the old ones appropriately, so unless you have a 
> ton (like thousands) of concurrently running applications connecting to it 
> there's little likelihood for it to OOM. At least that's my understanding.
>  
> -Andrew
>  
> 2014-10-22 15:51 GMT-07:00 Sameer Farooqui <same...@databricks.com 
> (mailto:same...@databricks.com)>:
> > Hi Keith,
> >  
> > Would be helpful if you could post the error message.
> >  
> > Are you running Spark in Standalone mode or with YARN?
> >  
> > In general, the Spark Master is only used for scheduling and it should be 
> > fine with the default setting of 512 MB RAM.
> >  
> > Is it actually the Spark Driver's memory that you intended to change?
> >  
> >  
> >  
> > ++ If in Standalone mode ++
> > You're right that SPARK_DAEMON_MEMORY set the memory to allocate to the 
> > Spark Master, Worker and even HistoryServer daemons together.
> >  
> > SPARK_WORKER_MEMORY is slightly confusing. In Standalone mode, it is the 
> > amount of memory that a worker advertises as available for drivers to 
> > launch executors. The sum of the memory used by executors spawned from a 
> > worker cannot exceed SPARK_WORKER_MEMORY.
> >  
> > Unfortunately, I'm not aware of a way to set the memory for Master and 
> > Worker individually, other than launching them manually. You can also try 
> > setting the config differently on each machine's spark-env.sh 
> > (http://spark-env.sh) file.
> >  
> >  
> > ++ If in YARN mode ++
> > In YARN, there is no setting for SPARK_DAEMON_MEMORY. Therefore this is 
> > only in the Standalone documentation.
> >  
> > Remember that in YARN mode there is no Spark Worker, instead the YARN 
> > NodeManagers launches the Executors. And in YARN, there is no need to run a 
> > Spark Master JVM (since the YARN ResourceManager takes care of the 
> > scheduling).
> >  
> > So, with YARN use SPARK_EXECUTOR_MEMORY to set the Executor's memory. And 
> > use SPARK_DRIVER_MEMORY to set the Driver's memory.
> >  
> > Just an FYI - for compatibility's sake, even in YARN mode there is a 
> > setting for SPARK_WORKER_MEMORY, but this has been deprecated. If you do 
> > set it, it just does the same thing as setting SPARK_EXECUTOR_MEMORY would 
> > have done.
> >  
> >  
> > - Sameer
> >  
> >  
> > On Wed, Oct 22, 2014 at 1:46 PM, Keith Simmons <ke...@pulse.io 
> > (mailto:ke...@pulse.io)> wrote:
> > > We've been getting some OOMs from the spark master since upgrading to 
> > > Spark 1.1.0.  I've found SPARK_DAEMON_MEMORY, but that also seems to 
> > > increase the worker heap, which as far as I know is fine.  Is there any 
> > > setting which *only* increases the master heap size?
> > >  
> > > Keith  
>  

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