Response Time-Optimized Distributed Cloud Resource Allocation - - PowerPoint PPT Presentation
Response Time-Optimized Distributed Cloud Resource Allocation - - PowerPoint PPT Presentation
Response Time-Optimized Distributed Cloud Resource Allocation Matthias Keller Holger Karl Computer Networks Group Universitt Paderborn Minimizing response times Latency-critical service Interactive, emergency service request t
Response Time-Optimized Distributed Cloud Resource Allocation
Minimizing response times
21
request t Response Time answer
DCC 2014
- Latency-critical service
- Interactive, emergency service
Response Time-Optimized Distributed Cloud Resource Allocation
Minimizing response times
22
request t
DCC 2014
- Latency-critical service
- Interactive, emergency service
Time to compute the answer answer Response Time
Response Time-Optimized Distributed Cloud Resource Allocation
Minimizing response times
23
request t
DCC 2014
answer Response Time Queuing System:
Time in Queue Processing Time Time in System (TIS)
+
Response Time-Optimized Distributed Cloud Resource Allocation
Minimizing response times
24
request t
DCC 2014
- Latency-critical service
- Interactive, emergency service
- Decision: Spend time on RTT or TIS
answer Response Time Queuing System:
Time in Queue Processing Time Time in System (TIS)
+
Response Time-Optimized Distributed Cloud Resource Allocation
Minimizing response times
25
request
DCC 2014
- Latency-critical service
- Interactive, emergency service
- Decision: Spend time on RTT or TIS
answer Response Time
Time in System (TIS)
10 20 30 40 50 arrival rate 2 4 6 8 10 12 14 average response time
RTT solution
Response Time-Optimized Distributed Cloud Resource Allocation
Example: RTT + TIS
26 DCC 2014
- Demand assignment
- Facility Location Solution with RTT only
Better
Response Time-Optimized Distributed Cloud Resource Allocation
Example: RTT + TIS
27 DCC 2014
- Demand assignment
- Facility Location Solution with RTT only
10 20 30 40 50 arrival rate 2 4 6 8 10 12 14 average response time
RTT solution RTT solution with TIS
Better
Response Time-Optimized Distributed Cloud Resource Allocation
Example: RTT + TIS
28 DCC 2014
- Demand assignment
- Facility Location Solution with RTT only
10 20 30 40 50 arrival rate 2 4 6 8 10 12 14 average response time
RTT solution RTT solution with TIS
Better Surprise at runtime
Response Time-Optimized Distributed Cloud Resource Allocation
Example: RTT + TIS
29 DCC 2014
- Demand assignment
- Facility Location Solution with RTT only
- With RTT + TIS
10 20 30 40 50 arrival rate 2 4 6 8 10 12 14 average response time
RTT solution RTT solution with TIS RTT+TIS solution
Better
Goal
30 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation
Given
- Network
- Data centres
Objective
- Minimize response time
Means
- Allocation of n VMs at data
centres
Goal
31 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation
Number of VMs Response Time Optimal Solutions
Given
- Network
- Data centres
Objective
- Minimize response time
Means
- Allocation of n VMs at data
centres
Characterise:
- How does response time
depend on number n of VMs?
Two Approaches
Accurate Solution
- Mixed Integer Convex Problem
- Convex TIS function for each
data centre
32 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation
0.00 0.30 0.60 0.90 utilization 2 4 6 8 10 time in system
- Tough to solve – slow?
Two Approaches
Accurate Solution
- Mixed Integer Convex Problem
- Convex TIS function for each
data centre
Approximate Solution
- Reformulation: Mixed Integer
Linear Problem
- Linearization of TIS function
33 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation
0.00 0.30 0.60 0.90 utilization 2 4 6 8 10 time in system 0.00 0.30 0.60 0.90 utilization 2 4 6 8 10 time in system
- riginal
uniform
- Accuracy? Speed?
- Tough to solve – slow?
Improve accuracy of linearization
- Objective:
- Minimize the maximum difference
- Control knobs
- Number of basepoints
- End point at asymptote
- Basepoint positions
34 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation
utilization 2 4 6 8 10 time in system
- riginal
uniform
0.00 0.30 0.60 0.90 0.0 0.5 1.0 1.5 2.0 2.5 difference to org.
Better
Improve accuracy of linearization
- Objective:
- Minimize the maximum difference
- Control knobs
- Number of basepoints
- End point at asymptote
- Basepoint positions
- Evaluation in Paper
35 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation
utilization 2 4 6 8 10 time in system
- riginal
uniform imamoto
0.00 0.30 0.60 0.90 0.0 0.5 1.0 1.5 2.0 2.5 difference to org.
Better
Evaluation of both approaches Convex Problem
- Reference Solution
- Tough to solve – slow?
Linear Problem
- Approximate Solution
- Accuracy? Speed?
36 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation
Linearization
Evaluation of both approaches Convex Problem
- Reference Solution
- Tough to solve – slow?
Linear Problem
- Approximate Solution
- Accuracy? Speed?
37 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation
Linearization Configurations
- 6 topologies, 12 – 54 nodes
- à 50 random demand realizations
- 10 data centre fix
Evaluation of both approaches Convex Problem
- Reference Solution
- Tough to solve – slow?
Linear Problem
- Approximate Solution
- Accuracy? Speed?
38 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation
Linearization Configurations
- 6 topologies, 12 – 54 nodes
- à 50 random demand realizations
- 10 data centre fix
VM limit: 5 – 10
Results – Approximation Ratio
39 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation dfn-bwin di-yuan norway atlanta zib54 ta2 topology 1.00 1.02 1.04 1.06 1.08 1.10 1.12 1.14 1.16 approximation ratio
Better
- approx. ratio = Resp.timeLinear
Resp.timeConvex
small large
Results – Approximation Ratio
40 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation dfn-bwin di-yuan norway atlanta zib54 ta2 topology 1.00 1.02 1.04 1.06 1.08 1.10 1.12 1.14 1.16 approximation ratio
Better
- approx. ratio = Resp.timeLinear
Resp.timeConvex
small large
Results – Runtime Ratio
41 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation dfn-bwin di-yuan norway atlanta zib54 ta2 topology 10-4 10-3 10-2 10-1 100 runtime ratio
Better
small large
runtime ratio = RuntimeLinear RuntimeConvex
Results – Runtime Ratio
42 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation dfn-bwin di-yuan norway atlanta zib54 ta2 topology 10-4 10-3 10-2 10-1 100 runtime ratio
Better
small large
runtime ratio = RuntimeLinear RuntimeConvex
RuntimeLinear RuntimeConvex 2s 0:28h 7s 1:03h 5s 1:15h
Results – Runtime Ratio
43 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation dfn-bwin di-yuan norway atlanta zib54 ta2 topology 10-4 10-3 10-2 10-1 100 runtime ratio
Better
small large
runtime ratio = RuntimeLinear RuntimeConvex
RuntimeLinear RuntimeConvex 2s 0:28h 7s 1:03h 5s 1:15h
Results – Optimal Solutions
- More Resources:
- Shorter time in queuing system
- VMs at closer data centres
44 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation
di-yuan norway dfn-bwin 5 6 7 8 9 10 5 6 7 8 9 10 5 6 7 8 9 10 Resource Limit (#VM) 50 100 150 200 250 300 350 Response Time (ms)
RTT TIS
Results – Optimal Solutions
- More Resources:
- Shorter time in queuing system
- VMs at closer data centres
45 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation
di-yuan norway dfn-bwin 5 6 7 8 9 10 5 6 7 8 9 10 5 6 7 8 9 10 Resource Limit (#VM) 50 100 150 200 250 300 350 Response Time (ms)
RTT TIS
In the paper…
- Convex/Linear Problem Formulation
- Facility Location Problem & queuing model
- P-median facility location + convex cost function
- P-median facility location + piecewise linear cost function
- Piecewise Linear Function: Minimize maximal difference
- Convexity Proof
- Evaluation
- Pareto optimal solutions
- Compare linear/convex problem
- Approx. Ratio
- Runtime
46 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation
In conclusion…
… adjust your latency-sensitive service:
- Faster!
- Adapt to demand fluctuations swiftly
- Accurate!
- With queuing delay – no surprises at runtime
47 DCC 2014 Response Time-Optimized Distributed Cloud Resource Allocation