Each reduce task should follow those phases:
1. Shuffle: copy intermediate results from all mappers and store them in
the memory buffer. Once the memory buffer is full, data copied from the
mappers are merged, combined and *spilled to disk*
2. Merge: Merge the spills
3. Reduce: call
HBase isn't an MR-dependent application, if you mean to ask that.
If your question is generally "What version of HBase can I use with
0.23", then 0.92 and 0.90 would both work against 0.23's HDFS, as
HBase is merely a HDFS client.
Qs:
- Are you facing issues using HBase with 0.23?
- Which compone
I tried installing hbase on top of hadoop 0.23.I get the following
error.Any suggestion
client1: Exception in thread "main" org.apache.hadoop.ipc.
RemoteException: Server IPC version 5 cannot communicate with client
version 3
client1: at org.apache.hadoop.ipc.Client.call(Client.java:740)
client
Hi,
Moving this to hbase user lists (bcc'd mapreduce-user). Please use the
right lists for your questions.
Have you tried following the last paragraph at the recommendations in
http://hbase.apache.org/book.html#hadoop? That is probably your
solution.
On Tue, Feb 7, 2012 at 8:22 PM, raghavendhra
Would anyone recommend a good book or online resource that specifically teaches
the .20 API as opposed to the .19 API? It's several years old and I've really
dropped the ball on this one.
As a followup...I'm mildly curious whether later versions (it's up to .23 I
believe) offer substantial dif
Hey Keith,
The new API is still unstable, and we continue to support the 0.19
stable (old) API even in 0.23, but here is a good guide:
http://www.slideshare.net/sh1mmer/upgrading-to-the-new-map-reduce-api
[The first part, from Owen]
On Wed, Feb 8, 2012 at 3:20 AM, Keith Wiley wrote:
> Would anyo
Hi all
i have an important question about mapreduce.
i have 2 hadoop mapreduce jobs. job1 has only mapper but no reducer. Job1
started and in its map() it is writing to a "file1" using
context(Arg1,Arg2). If i wanted to start job2 (immidietly after job1) ,
which should take the "file1" (output sti
Vamsi,
Is it not possible to express your M-M-R phase chain as a simple, single M-R?
Perhaps look at the ChainMapper class @
http://hadoop.apache.org/common/docs/current/api/org/apache/hadoop/mapred/lib/ChainMapper.html
On Wed, Feb 8, 2012 at 12:28 PM, Vamshi Krishna wrote:
> Hi all
> i have an
