hadoop cluster with mixed servers(different memory, speed, etc)

[Demai Ni <ni...@gmail.com>]

hi, folks,

I am wondering how hadoop cluster handle commodity hardware with different
speed, capacity .

This situation is happening and probably become very common soon. That a
cluster starts with 100 machines, and in a couple years, add another 100
machines. With Moore's law as an indicator, the new vs. old machines are at
least one generation apart. The situation get even more complex if the
'new' 100 join the cluster gradually. How hadoop handles this situation and
avoid the weakest link problem?

thanks

Demai