# freebsd-dtrace-tools

**Repository Path**: mirrors_amutu/freebsd-dtrace-tools

## Basic Information

- **Project Name**: freebsd-dtrace-tools
- **Description**: Collection of FreeBSD compatible DTrace scripts
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2025-07-25
- **Last Updated**: 2026-04-25

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

The collection contains FreeBSD compatible versions of common DTrace scripts.

# bsdrwsnoop

Outputs information about read/write calls by processes.
Also provides the possibility to filter output by a certain process
name or PID.

## Example:
    ./bsdrwsnoop
    ./bsdrwsnoop -p 1773
    ./bsdrwsnoop -n bash

# zfsslower.d

Shows ZFS read/write per process and file that are slower than
a certain number of milliseconds, provided as a command line argument

## Example:
    ./zfsslower.d 100

# zilt10k.d

Traces 10,000 IO events or 15 minutes, whichever comes first. Traces user-level events via the
ZFS/VFS interfaces, and is very verbose, because it includes ARC hits.

## Example:
    ./zilt10k.d

# vfssnoop.d

Observes VFS events (open, close, read, etc.) for running systems

## Example:
    ./vfssnoop.d

# zfstxgsyncbytes.d

Track the amount of outstanding dirty data within your storage pool to know which way to adjust zfs_dirty_data_max.
Requires the name of your zpool as a command line argument

## Example:
    ./zfstxgsyncbytes.d zroot

# zfstxgsyncduration.d

Measure the time to sync transaction groups, so that you know how long it would take to flush zfs_dirty_data_max bytes to disk.
Requires the name of your zpool as a command line argument

## Example:
    ./zfstxgsyncduration.d zroot

# spasync.d

Measure time, size, and number of IO operations, per spa_sync() call, which is the call which writes your txg out to disk.

## Example:
    ./spasync.d

# rw.d

Measure average latency, standard deviation, iops, and throughput with a distribution for IO operations. Useful for adjusting 
the following sysctls for your hardware:

	vfs.zfs.vdev.sync_read_min_active
	vfs.zfs.vdev.sync_read_max_active
	vfs.zfs.vdev.sync_write_min_active
	vfs.zfs.vdev.sync_write_max_active
	vfs.zfs.vdev.async_read_min_active
	vfs.zfs.vdev.async_read_max_active
	vfs.zfs.vdev.async_write_min_active
	vfs.zfs.vdev.async_write_max_active

## Example:
    ./rw.d

# zilstat

Measure ZIL activity to determine if an SLOG device will be a useful addition to your zpool

Adapted for FreeBSD from: http://www.richardelling.com/Home/scripts-and-programs-1/zilstat

Note: Requires FreeBSD 10.2 or later, otherwise the necessary function to trace is inlined.

## Example:
    ./zilstat

    ./zilstat -t 60    (print timestamps with output every 60 seconds)

	./zilstat 10 6     (print 10 samples 6 times)

	./zilstat -p zroot (print activity for a particular zpool)

	./zilstat -h       (print additional help and usage)