Hi

Currently CapacityScheduler does not have pre-emption. So basically when the 
Job1 starts finishing and freeing up the Job2's tasks will start getting 
scheduled. One way you can prevent that queue capacities are not elastic in 
nature is by setting max task limits on queues. That way your job1 will never 
execeed first queues capacity




On 4/28/11 11:48 PM, "Rosanna Man" <rosa...@auditude.com> wrote:

Hi all,

We are using capacity scheduler to schedule resources among different queues 
for 1 user (hadoop) only. We have set the queues to have equal share of the 
resources. However, when 1st task starts in the first queue and is consuming 
all the resources, the 2nd task starts in the 2nd queue will be starved from 
reducer until the first task finished. A lot of processing is being stuck when 
a large query is executing.

We are using 0.20.2 hive in amazon aws. We tried to use Fair Scheduler before 
but it gives an error when the mapper gives no output (which is fine in our use 
cases).

Anyone can give us some advice?

Thanks,
Rosanna

--
Sreekanth Ramakrishnan

Reply via email to