On 07/09/2013 05:36 PM, "Костарев А.Ф." wrote:
Hi Junping!
We have launched MapReduce tasks in YARN cluster. Its topology is
described in file topology.data. All files are here:
https://drive.google.com/folderview?id=0B1dEBvIR3qbpeFVxR0R6UXhyNEU&usp=sharing
And we found difference between MRv1 and YARN. In usual MapReduce tasks
were executed everywhere, but in YARN they are executed only within one
datacenter. It's shown on screenshots. Input file had replication factor 5.
So, is it possible to run 1 job not only in 1 datacenter but on all
servers of cluster at the same time?
One more question. In MapReduce in ouptut directory in HDFS there were:
_SUCCESS, log and part-r-xxxx. Now i can't find log. Is it in another
place or in YARN there isn't such a file?
Thank you for your prompt response
We will try to repeat the test on Thursday and show more details
On 07/09/2013 05:18 PM, Jun Ping Du wrote:
Hi Костарев,
I think it should work for YARN even YARN doesn't support layer
above rack (actually I am working on supporting more layers topology
for YARN at YARN-18) now.
Current YARN should just recognize your topology as three racks:
"dc1/rack1", "dc2/rack1", "dc2/rack2". Each node (NM) with free
resources should be assigned with containers in heartbeat with RM no
matter what locality level there. The only exception case should be:
1. no pending resource requests 2. NM capacity is too small to meet
resource request 3. delay scheduling is enabled and no data-local
attempt. In your case, I don't see anything stop task assignment on
a1 and a2. Anyone here can correct me if any misunderstanding here. :)
Anyway, I will give it a try (as your configuration) later to see
if some bugs in boundary cases there or it could be some
misconfiguration. Which minor version (2.0.x or trunk) you are using
now?
Thanks,
Junping
----- Original Message -----
From: "Костарев А.Ф." <[email protected]>
To: [email protected]
Sent: Tuesday, July 9, 2013 5:48:49 PM
Subject: Algorithm of distribution Map and Reduce tasks at various
topology of a network
Hi
I have claster in two datacenters
CLUSTER
|
+--------+---------+
| |
datacenter1 datacenter2
| |
rack1 rack1
| | |
+-a1 | +-b1
| | |
+-a2 | +-b3
|
rack2
+-b3
Cluster have file with repcica coefficient=5
All files's blocks resides on all servers of cluser.
When I work with standart MapReduce (MRv1) (called on b1) Map and
Rediuce task runs on all servers b1, b2, b3, a1, a2
When I work with YARN (MRv2) (called on b1) Map and Reduce task runs
only on b1, b2, b3
Can I run in YARN Map tasks on all servers?
--
Консультант 1-й категории
Костарев А.Ф.
