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I/O Trace Data Files

The following traces are free to download under the terms of the SNIA Trace Data Files Download License. Please note that cookies must be enabled within your browser in order to download traces.

The "Download Traces FAQs" provide information about the overall requirements and the procedure associated with downloading I/O Trace Data files from the IOTTA Repository.

We also have a spreadsheet containing information on some currently known traces.


The I/O Trace Data files have been segregated into several broad categories. These categories are typically, although not exclusively, defined by the measurement point at which the respective I/O trace was taken.

The categories (or types) of I/O traces include:

  • Application Traces [This category is currently empty]
    Application Traces record calls made by a specific application.
  • Block I/O Traces
    Block I/O Traces typically include block level (e.g., at the logical volume manager, disk driver, etc. level) and block protocol (e.g., SCSI, ATA, Fibre Channel) traces.
  • HPC Summaries
    Traces from HPC installations, generally expressed as statistical summaries rather than blow-by-blow event traces
  • Key-Value Traces
    Key-Value traces reflect activity directed to key-value stores.

    Related traces can also be found in the Parallel Traces section.

  • NFS Traces [This category is currently empty]
    Network File System Traces are typically those for NFS and CIFS and which reflect the protocol used by such network file systems.
  • Parallel Traces
    Parallel traces, generally taken from supercomputers or in large datacenters, record activity from multiple computers running in parallel.

    Similar traces can also be found in the Key-Value Traces section.

  • SSSI WIOCP Metrics
    SSSI WIOCP, the SNIA Solid State Storage Initiative (SSSI) Workload I/O Capture Program (WIOCP), collected already-summarized empirical metrics separately for both monitored devices and processes/applications. More information about the SSSI WIOCP can be found in the SSSI WIOCP FAQ and the 'Introduction to the SSSI WIOCP I/O Metrics' whitepaper.
  • Static Snapshots
    Static Snapshots are traces taken statically of a file system rather than of system calls.
  • System Call Traces
    System-Call I/O Traces typically reflect operating system calls to the file system.

    Some system-call traces can also be found in the Parallel Traces section.

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