what have we seen in class recently?
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What have we seen in class recently?. Daniel Shapiro. Exec time = (Task Crunch Amount)/(speed of PE) Makespan (longest critical path) Adjacent communication delay( i ,j ) = (Data amount)/(transfer rate between PEs) in-forest: each node has at most one immediate successor - PowerPoint PPT PresentationTRANSCRIPT
What have we seen in class recently?
Daniel Shapiro
• Exec time = (Task Crunch Amount)/(speed of PE)
• Makespan (longest critical path)• Adjacent communication delay(i,j) = (Data
amount)/(transfer rate between PEs)• in-forest: each node has at most one immediate successor• out-forest: each node has at most one immediate
predecessor
Time
• Completion Time = Execution Time + Total Communication Delay
• Total Communication Delay = Number of communication messages * delay per message
• Execution time maximum finishing time of any task
4
Scheduling inforest/outforest task graphs
1. The level of each node in the task graph is calculated as given above and used as each node’s priority
2. Whenever a processor becomes available, assign it the unexecuted ready task with the highest priority
5
Example
10
14 13
12
11
9
8 7
5
6
4
2
3
1
P1 P2 P3
1
2 3 4
5 6 7
8 9 10 11 12
13 14 Level 5
Level 4
Level 3
Level 2
Level 11
1 1 1
1 1 1
1 1 1 1 1
1 1
6
Scheduling interval ordered tasks
1. The number of successors of each node is used as each node’s priority
2. Whenever a processor becomes available, assign it the unexecuted ready task with the highest priority
7
Example
0 0 0
3 2 1
4 5 61
9
1 1
1 1 1
1 1 1
1 2 3
654
7 8
Time P1 P2
123
4 5 6
87 9
P30
1
2
3
8
a
b c
a
b
c
a
b
c
c
P1 P2 P1 P2
10
25
0
10
25
0
40
15
35c
40
50
x
x
x
Task Graph
Gantt Chart-2Gantt Chart-1
Task Exceution time
abc
101515
y
Arc Communication
(a,b) y
(a,c) x < y
x = 5 x = 25
30
Time Time
Communication Delay versus Parallelism
9
Clustering
a
bc
g
d e
f
a
bc
g
d e
f
a
bc
g
d e
f
(a)(b)
(c)
a
bc
g
d e
f
(d)
10
a
b c
a
b c
a
b
c
P1 P2 P1 P2
xx
Task Graph
x
a
No Duplication Task a is Duplicated
Duplications
Real Stuff
• http://www.site.uottawa.ca/eng/school/publications/techrep/2010/
Where is my T.A.?http://www.eng.tau.ac.il/~ieee/Convention/index.html
Instruction Set Extensions for Computation on Complex Floating Point Numbers
Parallel instruction set extension identification
Questions?
• Danke