-Re: rack awarness unexpected behaviour
Michael Segel 2013-10-03, 12:23
The rack aware script is an artificial concept. Meaning you can tell which machine is in which rack and that may or may not reflect where the machine is actually located.
The idea is to balance the number of nodes in the racks, at least on paper. So you can have 14 machines in rack 1, and 16 machines in rack 2 even though they may physically be 20 machines in rack 1 and 10 machines in rack 2.
On Oct 3, 2013, at 2:52 AM, Marc Sturlese <[EMAIL PROTECTED]> wrote:
> I've check it out and it works like that. The problem is, if the two racks
> have not the same capacity, one will have the disk space filled up much
> faster than the other (that's what I'm seeing).
> If one rack (rack A) has 2 servers of 8 cores with 4 reduce slots each and
> the other rack (rack B) has 2 servers of 16 cores with 8 reduce slots each,
> rack A will get filled up faster as rack B is writing more (because has more
> reduce slots).
> Could a solution be to modify the bash script used to decide to which
> replica write a block? Would use probability and give to rack B double
> chance to receive de write.
> View this message in context: http://lucene.472066.n3.nabble.com/rack-awareness-unexpected-behaviour-tp4086029p4093270.html
> Sent from the Hadoop lucene-users mailing list archive at Nabble.com.
The opinions expressed here are mine, while they may reflect a cognitive thought, that is purely accidental.
Use at your own risk.
michael_segel (AT) hotmail.com