## Bar Charts: Speedup vs. Number of Buckets for Different GPUs and Configurations
### Overview
The image presents six bar charts comparing the speedup achieved by three different algorithms (WMS, BMS, and RB-Sort) when processing data with varying numbers of buckets. The charts are organized in a 2x3 grid, with the top row showing results for "key-only" operations and the bottom row showing results for "key-value" operations. The columns represent different GPUs: Tesla K40c with ECC on, Tesla K40c with ECC off, and GeForce GTX 1080.
### Components/Axes
* **Y-axis (Speedup):** Linear scale from 0 to 10.
* **X-axis (Number of buckets (m)):** Categorical axis with values 2, 4, 8, 16, 32, 64, 128, and 256.
* **Legend (Top-Right of each chart):**
* WMS (Light Green)
* BMS (Medium Green)
* RB-Sort (Blue)
* **Chart Titles:**
* (a) Key-only: K40c (ECC on)
* (b) Key-only: K40c (ECC off)
* (c) Key-only: GTX 1080
* (d) Key-value: K40c (ECC on)
* (e) Key-value: K40c (ECC off)
* (f) Key-value: GTX 1080
### Detailed Analysis
**Chart (a): Key-only: K40c (ECC on)**
* **WMS (Light Green):** Starts at approximately 9.5 speedup for 2 buckets, decreasing to approximately 2.5 for 256 buckets.
* **BMS (Medium Green):** Starts at approximately 7.5 speedup for 2 buckets, decreasing to approximately 2 for 256 buckets.
* **RB-Sort (Blue):** Starts at approximately 4.5 speedup for 2 buckets, decreasing to approximately 1.75 for 256 buckets.
**Chart (b): Key-only: K40c (ECC off)**
* **WMS (Light Green):** Starts at approximately 8.25 speedup for 2 buckets, decreasing to approximately 2.25 for 256 buckets.
* **BMS (Medium Green):** Starts at approximately 7 speedup for 2 buckets, decreasing to approximately 2 for 256 buckets.
* **RB-Sort (Blue):** Starts at approximately 5 speedup for 2 buckets, decreasing to approximately 2.75 for 256 buckets.
**Chart (c): Key-only: GTX 1080**
* **WMS (Light Green):** Relatively stable, fluctuating between 5.5 and 6 speedup.
* **BMS (Medium Green):** Relatively stable, fluctuating between 5 and 5.5 speedup.
* **RB-Sort (Blue):** Starts at approximately 3.75 speedup for 2 buckets, decreasing to approximately 1.5 for 256 buckets.
**Chart (d): Key-value: K40c (ECC on)**
* **WMS (Light Green):** Starts at approximately 10 speedup for 2 buckets, decreasing to approximately 2.5 for 256 buckets.
* **BMS (Medium Green):** Starts at approximately 8 speedup for 2 buckets, decreasing to approximately 2 for 256 buckets.
* **RB-Sort (Blue):** Starts at approximately 4.5 speedup for 2 buckets, decreasing to approximately 1.75 for 256 buckets.
**Chart (e): Key-value: K40c (ECC off)**
* **WMS (Light Green):** Starts at approximately 8 speedup for 2 buckets, decreasing to approximately 2.25 for 256 buckets.
* **BMS (Medium Green):** Starts at approximately 6.75 speedup for 2 buckets, decreasing to approximately 2 for 256 buckets.
* **RB-Sort (Blue):** Starts at approximately 4.75 speedup for 2 buckets, decreasing to approximately 2.5 for 256 buckets.
**Chart (f): Key-value: GTX 1080**
* **WMS (Light Green):** Relatively stable, fluctuating between 5.5 and 6 speedup.
* **BMS (Medium Green):** Relatively stable, fluctuating between 5 and 5.5 speedup.
* **RB-Sort (Blue):** Starts at approximately 3.75 speedup for 2 buckets, decreasing to approximately 1.5 for 256 buckets.
### Key Observations
* For Tesla K40c (ECC on and off), both "key-only" and "key-value" operations show a decreasing speedup for all algorithms (WMS, BMS, and RB-Sort) as the number of buckets increases.
* For GeForce GTX 1080, the speedup for WMS and BMS is relatively stable across different numbers of buckets, while RB-Sort shows a decreasing trend.
* The WMS algorithm generally achieves the highest speedup, followed by BMS, and then RB-Sort.
* The performance difference between ECC on and ECC off for Tesla K40c appears to be relatively small.
### Interpretation
The data suggests that the performance of WMS and BMS algorithms is more sensitive to the number of buckets when running on Tesla K40c compared to GeForce GTX 1080. The RB-Sort algorithm consistently shows a decreasing speedup as the number of buckets increases across all GPUs and configurations. The relatively stable performance of WMS and BMS on the GTX 1080 might indicate that these algorithms are less affected by the number of buckets on this particular GPU, or that the GTX 1080's architecture handles the increasing number of buckets more efficiently. The small performance difference between ECC on and ECC off suggests that ECC has a minimal impact on the speedup for these algorithms and datasets. The choice of algorithm and GPU should be carefully considered based on the specific workload and the desired trade-off between speedup and resource utilization.
