0.6.0 User Manual

This manual provides a guide to using JDiskMark 0.6.0, a disk benchmarking tool. It covers the primary user interface elements and their functions, as seen in the application's main window.

Main Interface Overview

The JDiskMark interface is divided into several key sections:

• Menu Bar: Located at the top, it contains standard menus for File, Action, Options, and Help.
• Performance Graph: The large central area displays the performance results in real-time, charting bandwidth and access time over the measured samples.
• Settings Panel: On the right-hand side, this panel contains all the configurable settings for the benchmark tests.
• Benchmark Results: Results from the active or loaded benchmark
• Benchmark Tab: At the bottom, this table shows a history of completed benchmark runs with detailed metrics.
• Drive Location Tab: controls to configure the target drive location.
• Event Log Tab: message logging for benchmark

Performance Graph

This section is a visual representation of your disk's performance during a benchmark run.

• Y-Axis (Left): "Bandwidth MB/s" - Represents the data transfer speed in megabytes per second.
• Y-Axis (Right): "Access Time (ms)" - Represents the time it takes to access a data block, in milliseconds.
• X-Axis: Shows the test progress via sample count.
• Legend: The graph uses different colors and symbols to represent key metrics:
  • Write: A line showing the instantaneous write bandwidth.
  • Write Avg: A line showing the average write bandwidth over time. The final write avg is the result.
  • Write Max: A line showing the peak write bandwidth per thread.
  • Write Min: A line showing the min write bandwidth per thread.
  • Write Access: A series of dots representing individual data access times.
  • similar fields for Read metrics.

Settings Panel

This panel is where you configure the parameters for your benchmark tests.

• IO Mode: Select the type of operation to test.
  • Write: Tests the speed of writing data to the disk.
  • Read: Tests the speed of reading data from the disk.
  • Read & Write: Performs a Write test, clears the disk cache (or prompts user), followed by the Read test.
• Block Order: Determines the pattern in which data blocks are written or read.
  • Sequential: Data is accessed in a contiguous, ordered manner. This typically yields the highest performance numbers.
  • Random: Data is randomly accessed. This has a negative effect on mechanical platter drives.
• Blocks / Sample: The number of data blocks to process for each data point plotted on the graph.
• Block Size (KB): The size of each data block used in the test.
• No. Samples: The total number of samples to collect during the test run.
• Sample Size (KB): The total amount of data in each sample.
• Number Threads: The number of simultaneous threads used for the benchmark. This can significantly impact performance, especially on multi-core systems and with high-speed drives.
• Start Button: Click this button to begin the benchmark test.

Real-time Results & Summary

This section provides a summary of the test results, both during and after a run.

• Write IO (MB/s):
• Min: The lowest bandwidth recorded during the test.
• Max: The highest bandwidth recorded during the test.
• Avg: The average bandwidth for the entire test run.
• Acc (ms): Access time
• Min: The lowest access time recorded.
• Max: The highest access time recorded.
• Avg: The average access time for the entire test run.
• IOPS: Input/Output Operations Per Second. This metric measures how many read/write operations the drive can handle per second.

Saved Benchmarks (Tab)

This table provides a history of all benchmark runs performed during the current session.

• Drive Model: Identifies the disk being tested (e.g., "Samsung SSD 990 4TB").
• Usage: Shows the percentage of the drive's total capacity used.
• Mode: The IO Mode used for the test (e.g., "Write").
• Order: The Block Order used (e.g., "Sequential").
• Samples: The number of samples.
• Blocks (Size): The number of blocks and their size in KB.
• Thread: The number of threads used for the test.
• Start Time: The timestamp when the test began.
• Time (ms): The total duration of the benchmark run in milliseconds.
• Acc (ms): The average access time in milliseconds.
• Min/Max (MB/s): The minimum and maximum bandwidths achieved during the test.
• IO (MB/s): The final average bandwidth for the completed test.

Example of a Benchmark Run:

1. Select "Write" for the IO Mode.
2. Set Number Threads to "4".
3. Click the Start button.
4. Watch the performance graph as the test runs.
5. After completion, review the summary statistics in the Write IO and Acc sections.
6. The results will also be added as a new row in the Results Table at the bottom for historical comparison.