
545Toward Optimal Resource Provisioning
should be created and in the cost model. In the linear case, which is common as we
have observed, the cost model can be further simplied to
TMmR
M
m
MR
m
m
R
MM
MR M
2012 3
456
(,,)
log
/
=+ ++
+++
ββ ββ
βββ+
β
7
R
,
(17.10)
17.4 LEARNING THE MODEL
With the formulation of the cost function in terms of input variables M, m, and R, we
need to learn the parameters β
i
. Note that β
i
should be different from application to
application. We design a learning procedure as follows.
First, for a specic MapReduce program, we randomly choose the variables M, m,
and R from certain ranges. For example, m and R (i.e., r) are chosen with ...