Foothills 94

Foothills 94 Dataset - 2D
(2nd order time, 8th order space)

 



 
 
277 shots at:
35.8 seconds / shot (single GT200) 
FUTURE seconds / shot (x CPU cores, TBD GHz)

Document Revision:  V1.10 
Last Updated: 
December 10, 2008 
RTM Orders: 
2nd Time, 8th Space 
SW Release Used: 
“Columbia” 
SW Release Date: 
November 7, 2008 
Benchmark Status:  
Public, Non-Confidential 

 

RTM Model Definition

Problem Definition Parameters    
2D line length 25.0 km  
Survey depth 10.0 km  
Total number of shots 277 shots  
Number of receivers, per shot 246-480 receivers/shot  
       
Minimum shot offset 0.0 m  
Maximum shot offset 3.600.0 m  
       
Trace sampling interval 4.0 milliseconds  
Trace length 5.0 seconds  
Number of samples 1,250 samples  
       
Migration frequency 50.0 Hz  
Maximum velocity 6,000 m/s  
Minimum velocity (water) 3,600 m/s  
Maximum wavelength 120 m [fn for migration freq and max. velocity]
Minimum wavelength 72 m [fn for migration freq and min. velocity]
       
Temporal order 2 nd  
Spatial order 8 th  
Grid points per wavelength 4.0 points/lambda [dispersion-free for minimum wavelength]
Maximum allowable cell size (for dispersion) 18.0 m [dispersion-free for minimum wavelength]
Working cell size 4 m [cell size actually used in the migration]
       
dt 0.5 miliseconds  
Simulation timesteps 10,000 timesteps  
       
RTM Model Assumptions Parameters    
Maximum volumes in memory 6   [6, +1 for density, +6 for (VTI) anisotrophy]
       
RTM Boundaries      
Number of sponge boundary layers, each x-axis 30    
Number of sponge boundary layers, Zmin 30    
Number of sponge boundary layers,Zmax 30    
Extra cells at EACH boundary due to FD stencil 4   [2 cells for 4th-order-in-space, 4 cells for 8th-order-in-space]
       
Size of RTM domain 15.6 million cells  
Size of RTM domain, including boundaries 16.2 million cells  
Memory high watermark, including boundaries 371.4 Mbytes [given num. volumes stored, single precision]
       
Calculations      
"Normal" cells, X 6,250    
"Normal" cells, Z 2,500    
Total "normal" cell count 15,625,000    
Cells including boundaries, X 6,318    
Cells including boundaries, Z 2,568    
Total Cell Count, including boundaries 16,224,624    
Memory occupation, including boundaries 389,390,976 bytes  
Additional fields stored 1,199,248    
Memory occupation, additional storage required (MB) 4.57   Mbytes  

 

GPU Performance

RTM Parameters (carry over)      
Size of RTM domain, including boundaries 15.6 million cells  
Memory high water mark, including boundaries 371.4 Mbytes  
Total number of shots 277 shots  
       
Single GPU specifications      
GPU memory (GB) 3.6 GB [next gen h/w from NVIDIA, GT200 = 4GB with 0.9 Safety Factor]
       
"Accelerated Node" definition      
CPU Server hosts per "Tesla" (GPU Server)  2   NOT USED
Number of GPU servers 1   NOT USED
Individual GPU's per GPU server 4   NOT USED
       
Single GPU Configuration      
Total time to migrate single shot 35.8 seconds [Single NVIDIA GT200]
Time to migrate all shots 2.8 hours [Assumes none of the shots are migrated on parallel equipment]
       
Forward Propagation (and Illumination Calculation)      
Total time for forward pass 13.0351 seconds  
Time per iteration (forward) 0.00130351 seconds [Acceleware recommends that this is the best metric to use for performance comparisons]
Throughput (NOT including boundary cells) 1,323 Mcells/s [Boundary cells are included in the time but not in the number of cells updated]
Throughput (INCLUDING boundary cells) 1,476 Mcells/s  
       
Reverse Propagation (inc. Correlation)      
Total time, for reverse pass 22.7235 seconds  
Time per iteration (reverse) 0.00227235 seconds  [Acceleware recommends that this is the best metric to use for performance comparisons]
Throughput (NOT Including Boundary Cells) 759 Mcells/s [NB Two identically sized RTM domains exist in memory, at the same time, during this stage of the migration. Cells for only one of the domains are counted]
Throughput (INCLUDING Boundary Cells) 847 Mcells/s  

 

 

 "Hard" Velocity Model Migrated with “Hard” Velocity Model
   
 “Smoothed” Velocity Model  Migrated with “Smoothed” Velocity Model

 

Summary of Benchmark Results

      Size of Domain   Performance
            "Normal" Cells Including Boundaries       Time per iteration
  Temporal Order Spacial Order X Y Z (Mcells) (Mcells) Memory High Water Mark Number of GPU's per shot Total Time, per Shot Forward
(seconds)
Reverse
(seconds)
BP Dataset 2D 2nd 8th 16,850 - 2,975 50.1 51.5  1.15 Gbytes 1 Under Construction
Foothills Dataset - 2D 2nd 8th 6,250 - 2,500 15.6 16.2 371.4 Mbytes 1 35.8 seconds 0.0013035 0.0022724
Marmousi 2D 2nd 8th 2,300 - 750 1.73 1.94 44.3 Mbytes 1 39.0 seconds 0.0014268 0.0024758
SEG Salt, A1 - 3D 2nd 4th 100 676 185 12.5 30.2  691.6 Mbytes 1 144.8 seconds 0.0222250 0.0357102
SEG Salt, A2 - 3D 2nd 4th 676 50 185 6.3 21.0 480.8 Mbytes 1 116.7 seconds 0.0175312 0.0291397
SEG Salt, B1 - 3D     Under Construction   Under Construction

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