Image Processing Reference
In-Depth Information
Table 7.1 Parameters used in the utilized scenario
d
i
Transmission (device) delay
d
j
Reception (device) delay
r
k
(P)
Rack of
P
static and mobile devices
r
i
Rack redundant resources that a mobile device can claim
a
j
Claimed resource/partitionable task
s
j
i
Number of servers in rack
r
k
hosting application resource/task
a
j
S
aj
The number of servers hosting application resource/task
S
t
Service time for completing a task
P
d
Processing delay of
S
aj
MN
m
Mobile node claiming resources
s
Sequential partitions
another terminal, according to the measures of the available resources and the
minimized
S
t
and
P
d
(see Table
7.1
).
Moreover, this work enables the rack utility maximization (RUM), which aims
at maximizing the utilization of the rack in order to be able to host processes sent by
mobile devices. The RUM is based on the index of remaining
r
i
resources that each
MN
m
can claim, and on the utilization degree of each cloud rack. Considering the
above parameters, in order to maximize the available resources on the rack, the
following should be satisfied:
max
X
r2R
U
r
XðÞ8
Λ
LUM
:
A
x
C
,
x
0
ð
7
:
1
Þ
where
r
denotes the index of the
MN
m
source node,
χ
r
represents the transmission
rate of MN
m
(
r
),
C
is a vector containing the associated capacities of all links of
MN
m
(
r
), and
U
r
(
χ
r
) is the utility of node
r
when transmitting at rate
χ
r
. In order to
avoid mobile nodes
resources execution failure, the resources (that are to be run on
a node) are being partitioned and distributed to
K
MN
i
terminals in a
r
k
,
whereas the
cloud scheduler is acting as a distributor of the file chunks on
r
k
. The distribution
policy (shown in Fig.
7.2
) is based on the utilization of the
K
MN
m
on
r
k
,
and the
scheduled resources with the time frame
t
. The scheduling policy is shown in
Fig.
7.3
, where if the resources (memory and capacity limitations) are not met
and the task-partitioned pieces are missing, then the cloud scheduler re-assigns
the claimed chunks to other mobile terminals satisfying the delay requirements. The
delay that the transmission experiences
'
d
p
, where
d
p
is the
maximum delay in the end-to-end path from a source to a destination and is
evaluated as:
δ
ij
should satisfy the
δ
ij
<
X
i
1
i¼
0
δ
i
þ
max
X
r2R
d
p
¼
T
i
8
U
r
χðÞ
ð
7
:
2
Þ
