blkparse

blkparse [options] [device...]

blkparse produces formatted output from event streams recorded by blktrace. It combines event streams from multiple CPUs and devices, converting machine-readable trace data into human-readable format.The tool is essential for analyzing block I/O patterns, debugging storage performance issues, and understanding how the Linux I/O scheduler processes requests.

-i file

Base name for input files (default device.blktrace.cpu); use "-" for live stdin

Output file (default: stdout)

Prepend this directory to the input file names

Dump a merged binary event stream to file

Custom output format string for all events

Output format string for a specific event type

Quiet mode; only print summary at end

Show per-program (per-process) statistics

Track I/O timing; display time deltas per I/O

Limit output to a time window; end or start:end in nanoseconds

Add mask to the current trace action filter

Set the trace action filter to hexmask

More verbose output

Q - Queued: Intent to queue I/O notedI - Inserted: Request sent to I/O schedulerD - Issued: Request sent to driverC - Complete: Request completedM - Back merge: Request merged with existingF - Front merge: Request merged at frontP - Plug: Queue pluggedU - Unplug: Queue unplugged

Requires trace data from blktrace to function. Trace files can become very large for busy systems. Running blktrace requires root privileges. Output can be overwhelming; use format options to limit fields.

blkparse was written by Jens Axboe, Alan D. Brunelle, and Nathan Scott as part of the blktrace toolkit. It was developed to provide detailed I/O tracing capabilities for Linux storage subsystem analysis and debugging.

blktrace(8), btrace(8), btt(1), iostat(1)

Source code