On 28/03/11 23:34, JunYoung Kim wrote:
hi,
this linke is about hadoop usage for the good practices.
http://developer.yahoo.com/blogs/hadoop/posts/2010/08/apache_hadoop_best_practices_a/
by Arun C Murthy
if I want to use about 50,000 counters for a job, does it cause serious
performance down?
Yes, you will use up lots of JT memory and so put limits on the overall
size of your cluster.
If you have a small cluster and can crank up the memory settings on the
JT to 48 GB this isn't going to be an issue, but as Y! are topping out
at these numbers anyway, lots of counters just overload them.
