Eric,

Thanks for the quick reply.  Another question - My cluster has over 80 cpus 
available.  Suppose I create something like 50 splits across the 7 servers - I 
will increase my map job count accordingly.  What are your thoughts on this?

Thanks,
Ralph

__________________________________________________
Ralph Perko
Pacific Northwest National Laboratory



From: Eric Newton <[email protected]<mailto:[email protected]>>
Reply-To: "[email protected]<mailto:[email protected]>" 
<[email protected]<mailto:[email protected]>>
To: "[email protected]<mailto:[email protected]>" 
<[email protected]<mailto:[email protected]>>
Subject: Re: table splits

You need to estimate the size of the split.  First, get the id of the table 
with "tables -l" in the accumulo shell.

Then, find out the size of table in hdfs:

 $ hadoop fs -dus /accumulo/tables/<id>

Divide by 7, and use that as the split size:

 shell> config -t mytable -s table.split.threshold=newsize

The table will automatically split out.  Afterwards, you can then raise the 
split size to keep it from splitting until it gets much bigger:

shell> config -t mytable -s table.split.threshold=1G

-Eric

On Mon, May 21, 2012 at 12:24 PM, Perko, Ralph J 
<[email protected]<mailto:[email protected]>> wrote:
Hi,

I am looking for advice on how to best layout my table splits.  I have a 7 node 
cluster and my table contains ~10M records.  I would like to split the table 
equally across all the servers however I see no utility to do this in this 
manner.  I understand I can create splits for some letter range but I was 
hoping for some way to have accumulo create "n" equal splits.  Is this 
possible?  Right now the best way I see to handle this is to write a utility 
that iterates the table, keeps a count and at some given value (table size/ 
split count) spits out the beginning and end row and then I create the split 
manually.

Thanks,
Ralph

__________________________________________________
Ralph Perko
Pacific Northwest National Laboratory



Reply via email to