DDS-3 Back-up Parameter Optimization
6
Donald Kerns - [email protected] MSIE 202 © Donald Kerns, 2001 DDS-3 Back-up DDS-3 Back-up Parameter Optimization Parameter Optimization San Jose State University ISE 202 Donald Kerns 12/7/2001
-
Upload
samantha-branch -
Category
Documents
-
view
27 -
download
1
description
DDS-3 Back-up Parameter Optimization. San Jose State University ISE 202 Donald Kerns 12/7/2001. DDS-3 Back-up Parameter Optimization. Problem Statement : Current weekly server back-ups are taking ~15 hours. This reduces maximum possible server availability and eats into productive time. - PowerPoint PPT Presentation
Transcript of DDS-3 Back-up Parameter Optimization
1Donald Kerns - [email protected]
MSIE 202
© Donald Kerns, 2001
DDS-3 Back-upDDS-3 Back-upParameter OptimizationParameter Optimization
DDS-3 Back-upDDS-3 Back-upParameter OptimizationParameter Optimization
San Jose State University
ISE 202
Donald Kerns
12/7/2001
2Donald Kerns - [email protected]
MSIE 202
© Donald Kerns, 2001
DDS-3 Back-up Parameter OptimizationDDS-3 Back-up Parameter Optimization
Problem Statement:• Current weekly server back-ups are taking ~15 hours.• This reduces maximum possible server availability and eats into productive time.
Goal/Objective Statement:• Back-ups to take no longer than 8 hours/week (can happen completely overnight).• Increase maximum possible server availability from 92% to >= 95%.
Projected Business Benefits:Roughly $55K/year in labor savings.
Team:Donald Kerns
3Donald Kerns - [email protected]
MSIE 202
© Donald Kerns, 2001
DesignDesignDesignDesign
Compression Block Size FIFO Size Time(on/off) (KB) (MB) (sec)
0 4096 4 1245.041 4096 4 982.620 65536 4 618.031 65536 4 344.260 4096 256 1206.411 4096 256 961.870 65536 256 620.151 65536 256 345.610 4096 4 1202.221 4096 4 943.030 65536 4 617.951 65536 4 343.860 4096 256 1199.571 4096 256 941.160 65536 256 619.671 65536 256 346.92
• 23 (2 replicates)
• no confounding
• On/Off nature of compression made center points problematic
• Literature claimed a 5% effect of FIFO size
• 16 runs ~= 9 hours
• fits overnight
4Donald Kerns - [email protected]
MSIE 202
© Donald Kerns, 2001
Data and AnalysisData and Analysis
706050403020100
B
A
BC
AB
C
AC
ABC
Pareto Chart of the Standardized Effects(response is Time, Alpha = .10)
A: CompressB: Block SiC: FIFO Siz
Fractional Factorial Fit: Time versus Compression, Block Size, FIFO Size
Estimated Effects and Coefficients for Time (coded units)
Term Effect Coef PConstant 783.6 0.000Compression -265.0 -132.5 0.000Block Size -603.2 -301.6 0.000FIFO Size -7.0 -3.5 0.398Compress*Block Si -8.8 -4.4 0.290Compress*FIFO Siz 2.4 1.2 0.765Block Si*FIFO Siz 9.0 4.5 0.280Compress*Block Si*FIFO Siz -2.3 -1.1 0.779
3020100-10-20
2
1
0
-1
-2
Nor
mal
Sco
re
Residual
Normal Probability Plot of the Residuals(response is Time)
5Donald Kerns - [email protected]
MSIE 202
© Donald Kerns, 2001
Analysis (cont)Analysis (cont)Analysis (cont)Analysis (cont)
• Initial result
• FIFO Size not significant
• Compression should be on
• Further investigate block size
• Chose factor of 2 block sizes
• Plot speed vs. size
• Highest speed starts at 32KB
6Donald Kerns - [email protected]
MSIE 202
© Donald Kerns, 2001
ConclusionsConclusionsConclusionsConclusions
Baseline OptimizedBlock size 512 B 32 KBCompression off onFIFO Size 4 MB 4 MB
Speed (MB/min) 22 <125,127>
Weekly Availability 91% 98%
New settings:
• Increase maximum server availability from 91% to 98%.
• Allow back-ups to be completely performed overnight.
