Does MMap works on the Virtual Box?

2013-08-16 Thread vibhoreng04
Hi All,

I have a big index of 256 GB .Right now it is on one physical box of 256 GB
RAM . I am planning to virtualize it to the size of 32 GB Ram*8
boxes.Whether the MMap will work regardless in this condition ?

Vibhor Jaiswal



--
View this message in context: 
http://lucene.472066.n3.nabble.com/Does-MMap-works-on-the-Virtual-Box-tp4085154.html
Sent from the Solr - User mailing list archive at Nabble.com.


Re: Does MMap works on the Virtual Box?

2013-08-16 Thread Shawn Heisey

On 8/16/2013 1:02 PM, vibhoreng04 wrote:

I have a big index of 256 GB .Right now it is on one physical box of 256 GB
RAM . I am planning to virtualize it to the size of 32 GB Ram*8
boxes.Whether the MMap will work regardless in this condition ?


As far as MMap goes, if the operating system you are running is 64-bit, 
your Java is 64-bit, and the OS supports MMap (which almost every 
operating system does, including Linux and Windows), then you'd be fine.


If you have the option of running Solr on bare metal vs. running on the 
same hardware in a virtualized environment, you should always choose the 
bare metal.


I had a Solr installation with a sharded index.  When I first set it up, 
I used virtual machines, one Solr instance and shard per VM.  Half the 
VMs were running on one physical box, half on another.  For redundancy, 
I had a second pair of physical servers doing the same thing, each with 
VMs representing half the index.


That same setup now runs on bare metal -- the exact same physical 
machines, in fact.  The index arrangement is nearly the same as before, 
except it uses multicore Solr, one instance per machine.


Removing the virtualization layer helped performance quite a bit. 
Average QTimes went way down and it took less time to do a full index 
rebuild.


Thanks,
Shawn



Re: Does MMap works on the Virtual Box?

2013-08-16 Thread Paul Masurel
Hi,

You can MMAP a size bigger than your memory without having any problem.
Part of your file will just not be loaded into RAM, because you don't
access it too often.

If you are short in memory, consider deactivating page Host IO Caching, as
it will be only redundant with your guest
OS page cache.

Regards,

Paul



On Fri, Aug 16, 2013 at 10:26 PM, Shawn Heisey s...@elyograg.org wrote:

 On 8/16/2013 1:02 PM, vibhoreng04 wrote:

 I have a big index of 256 GB .Right now it is on one physical box of 256
 GB
 RAM . I am planning to virtualize it to the size of 32 GB Ram*8
 boxes.Whether the MMap will work regardless in this condition ?


 As far as MMap goes, if the operating system you are running is 64-bit,
 your Java is 64-bit, and the OS supports MMap (which almost every operating
 system does, including Linux and Windows), then you'd be fine.

 If you have the option of running Solr on bare metal vs. running on the
 same hardware in a virtualized environment, you should always choose the
 bare metal.

 I had a Solr installation with a sharded index.  When I first set it up, I
 used virtual machines, one Solr instance and shard per VM.  Half the VMs
 were running on one physical box, half on another.  For redundancy, I had a
 second pair of physical servers doing the same thing, each with VMs
 representing half the index.

 That same setup now runs on bare metal -- the exact same physical
 machines, in fact.  The index arrangement is nearly the same as before,
 except it uses multicore Solr, one instance per machine.

 Removing the virtualization layer helped performance quite a bit. Average
 QTimes went way down and it took less time to do a full index rebuild.

 Thanks,
 Shawn




-- 
__

 Masurel Paul
 e-mail: paul.masu...@gmail.com