lttnganalyses 0.5.4

LTTng analyses

LTTng analyses
**************

.. image:: https://img.shields.io/pypi/v/lttnganalyses.svg?label=Latest%20version
:target: https://pypi.python.org/pypi/lttnganalyses
:alt: Latest version released on PyPi

.. image:: https://travis-ci.org/lttng/lttng-analyses.svg?branch=master&label=Travis%20CI%20build
:target: https://travis-ci.org/lttng/lttng-analyses
:alt: Status of Travis CI

.. image:: https://img.shields.io/jenkins/s/https/ci.lttng.org/lttng-analyses_master_build.svg?label=LTTng%20CI%20build
:target: https://ci.lttng.org/job/barectf
:alt: Status of LTTng CI

The **LTTng analyses** are a set of various executable analyses to
extract and visualize monitoring data and metrics from
`LTTng <http://lttng.org/>`_ kernel traces on the command line.

As opposed to other "live" diagnostic or monitoring solutions, this
approach is based on the following workflow:

#. Record your system's activity with LTTng, a low-overhead tracer.
#. Do whatever it takes for your problem to occur.
#. Diagnose your problem's cause **offline** (when tracing is stopped).

This solution allows you to target problems that are hard to find and
to "dig" until the root cause is found.

.. contents::
:local:
:depth: 2
:backlinks: none


Install LTTng analyses
======================

.. NOTE::

The version 2.0 of `Trace Compass <http://tracecompass.org/>`_
requires LTTng analyses 0.4: Trace Compass 2.0 is not compatible
with LTTng analyses 0.5 and after.

In this case, we suggest that you install LTTng analyses from the
``stable-0.4`` branch of the project's Git repository (see
`Install from the Git repository`_). You can also
`download <https://github.com/lttng/lttng-analyses/releases>`_ the
latest 0.4 release tarball and follow the
`Install from a release tarball`_ procedure.


Required dependencies
---------------------

- `Python <https://www.python.org/>`_ ≥ 3.4
- `setuptools <https://pypi.python.org/pypi/setuptools>`_
- `Babeltrace <http://diamon.org/babeltrace/>`_ ≥ 1.2 with Python
bindings (``--enable-python-bindings`` when building from source)


Optional dependencies
---------------------

- `LTTng <http://lttng.org/>`_ ≥ 2.5: to use the
``lttng-analyses-record`` script and to trace the system in
general
- `termcolor <https://pypi.python.org/pypi/termcolor/>`_: color
support
- `progressbar <https://pypi.python.org/pypi/progressbar/>`_:
terminal progress bar support (this is not required for the
machine interface's progress indication feature)


Install from PyPI (online repository)
-------------------------------------

To install the latest LTTng analyses release on your system from
`PyPI <https://pypi.python.org/pypi/lttnganalyses>`_:

#. Install the required dependencies.
#. **Optional**: Install the optional dependencies.
#. Make sure ``pip`` for Python 3 is installed on your system. The
package is named ``python3-pip`` on most distributions
(``python-pip`` on Arch Linux).
#. Use ``pip3`` to install LTTng analyses:

.. code-block:: bash

sudo pip3 install --upgrade lttnganalyses


Install from a release tarball
------------------------------

To install a specific LTTng analyses release (tarball) on your system:

#. Install the required dependencies.
#. **Optional**: Install the optional dependencies.
#. `Download <https://github.com/lttng/lttng-analyses/releases>`_ and
extract the desired release tarball.
#. Use ``setup.py`` to install LTTng analyses:

.. code-block:: bash

sudo ./setup.py install


Install from the Git repository
-------------------------------

To install LTTng analyses from a specific branch or tag of the
project's Git repository:

#. Install the required dependencies.
#. **Optional**: Install the optional dependencies.
#. Make sure ``pip`` for Python 3 is installed on your system. The
package is named ``python3-pip`` on most distributions
(``python-pip`` on Arch Linux).
#. Use ``pip3`` to install LTTng analyses:

.. code-block:: bash

sudo pip3 install git+git://github.com/lttng/lttng-analyses.git@master

Replace ``master`` with the desired branch or tag name to install
in the previous URL.


Install on Ubuntu
-----------------

To install LTTng analyses on Ubuntu ≥ 12.04:

#. Add the *LTTng Latest Stable* PPA repository:

.. code-block:: bash

sudo apt-get install -y software-properties-common
sudo apt-add-repository -y ppa:lttng/ppa
sudo apt-get update

Replace ``software-properties-common`` with
``python-software-properties`` on Ubuntu 12.04.
#. Install the required dependencies:

.. code-block:: bash

sudo apt-get install -y babeltrace
sudo apt-get install -y python3-babeltrace
sudo apt-get install -y python3-setuptools
#. **Optional**: Install the optional dependencies:

.. code-block:: bash

sudo apt-get install -y lttng-tools
sudo apt-get install -y lttng-modules-dkms
sudo apt-get install -y python3-progressbar
sudo apt-get install -y python3-termcolor
#. Install LTTng analyses:

.. code-block:: bash

sudo apt-get install -y python3-lttnganalyses


Install on Debian "sid"
-----------------------

To install LTTng analyses on Debian "sid":

#. Install the required dependencies:

.. code-block:: bash

sudo apt-get install -y babeltrace
sudo apt-get install -y python3-babeltrace
sudo apt-get install -y python3-setuptools
#. **Optional**: Install the optional dependencies:

.. code-block:: bash

sudo apt-get install -y lttng-tools
sudo apt-get install -y lttng-modules-dkms
sudo apt-get install -y python3-progressbar
sudo apt-get install -y python3-termcolor
#. Install LTTng analyses:

.. code-block:: bash

sudo apt-get install -y python3-lttnganalyses


Record a trace
==============

This section is a quick reminder of how to record an LTTng kernel
trace. See LTTng's `quick start guide
<http://lttng.org/docs/v2.7/#doc-getting-started>`_ to familiarize
with LTTng.


Automatic
---------

LTTng analyses ships with a handy (installed) script,
``lttng-analyses-record``, which automates
the steps to record a kernel trace with the events required by the
analyses.

To use ``lttng-analyses-record``:

#. Launch the script:

.. code-block:: bash

lttng-analyses-record
#. Do whatever it takes for your problem to occur.
#. When you are done recording, press Ctrl+C where the script is
running.


Manual
------

To record an LTTng kernel trace suitable for the LTTng analyses:

#. Create a tracing session:

.. code-block:: bash

sudo lttng create
#. Create a channel with a large sub-buffer size:

.. code-block:: bash

sudo lttng enable-channel --kernel chan --subbuf-size=8M
#. Create event rules to capture the needed events:

.. code-block:: bash

sudo lttng enable-event --kernel --channel=chan block_bio_backmerge
sudo lttng enable-event --kernel --channel=chan block_bio_remap
sudo lttng enable-event --kernel --channel=chan block_dirty_buffer
sudo lttng enable-event --kernel --channel=chan block_rq_complete
sudo lttng enable-event --kernel --channel=chan block_rq_issue
sudo lttng enable-event --kernel --channel=chan irq_handler_entry
sudo lttng enable-event --kernel --channel=chan irq_handler_exit
sudo lttng enable-event --kernel --channel=chan lttng_statedump_block_device
sudo lttng enable-event --kernel --channel=chan lttng_statedump_file_descriptor
sudo lttng enable-event --kernel --channel=chan lttng_statedump_process_state
sudo lttng enable-event --kernel --channel=chan mm_page_alloc
sudo lttng enable-event --kernel --channel=chan mm_page_free
sudo lttng enable-event --kernel --channel=chan mm_vmscan_wakeup_kswapd
sudo lttng enable-event --kernel --channel=chan net_dev_xmit
sudo lttng enable-event --kernel --channel=chan netif_receive_skb
sudo lttng enable-event --kernel --channel=chan sched_process_exec
sudo lttng enable-event --kernel --channel=chan sched_process_fork
sudo lttng enable-event --kernel --channel=chan sched_switch
sudo lttng enable-event --kernel --channel=chan softirq_entry
sudo lttng enable-event --kernel --channel=chan softirq_exit
sudo lttng enable-event --kernel --channel=chan softirq_raise
sudo lttng enable-event --kernel --channel=chan writeback_pages_written
sudo lttng enable-event --kernel --channel=chan --syscall --all
#. Start recording:

.. code-block:: bash

sudo lttng start
#. Do whatever it takes for your problem to occur.
#. Stop recording and destroy the tracing session to free its
resources:

.. code-block:: bash

sudo lttng stop
sudo lttng destroy


See the `LTTng Documentation <http://lttng.org/docs/>`_ for other
use cases, like sending the trace data over the network instead of
recording trace files on the target's file system.


Analyze
=======

The **LTTng analyses** are a set of various command-line
analyses. Each analysis accepts the path to a recorded trace
(see `Record a trace`_) as its argument, as well as various command-line
options to control the analysis and its output.

Many command-line options are common to all the analyses, so that you
can filter by timerange, process name, process ID, minimum and maximum
values, and the rest. Also note that the reported timestamps can
optionally be expressed in the GMT time zone.

Each analysis is installed as an executable starting with the
``lttng-`` prefix.

.. list-table:: Available LTTng analyses
:header-rows: 1

* - Command
- Description
* - ``lttng-cputop``
- Per-TID, per-CPU, and total top CPU usage.
* - ``lttng-iolatencyfreq``
- I/O request latency distribution.
* - ``lttng-iolatencystats``
- Partition and system call latency statistics.
* - ``lttng-iolatencytop``
- Top system call latencies.
* - ``lttng-iolog``
- I/O operations log.
* - ``lttng-iousagetop``
- I/O usage top.
* - ``lttng-irqfreq``
- Interrupt handler duration frequency distribution.
* - ``lttng-irqlog``
- Interrupt log.
* - ``lttng-irqstats``
- Hardware and software interrupt statistics.
* - ``lttng-memtop``
- Per-TID top allocated/freed memory.
* - ``lttng-schedfreq``
- Scheduling latency frequency distribution.
* - ``lttng-schedlog``
- Scheduling top.
* - ``lttng-schedstats``
- Scheduling latency stats.
* - ``lttng-schedtop``
- Scheduling top.
* - ``lttng-syscallstats``
- Per-TID and global system call statistics.

Each command also has its corresponding JSON-based machine interface
version with the ``-mi`` suffix. For LTTng analyses 0.5 and after,
this machine interface is specified by the
`LTTng analyses machine interface (LAMI)
<https://github.com/lttng/lami-spec/blob/master/lami.adoc>`_ document.

Use the ``--help`` option of any command to list the descriptions
of the possible command-line options.

.. NOTE::

You can set the ``LTTNG_ANALYSES_DEBUG`` environment variable to
``1`` when you launch an analysis to enable a debug output.


Examples
========

This section shows a few examples of using some LTTng analyses.

I/O
---

Partition and system call latency statistics
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: bash

lttng-iolatencystats /path/to/trace

::

Timerange: [2015-01-06 10:58:26.140545481, 2015-01-06 10:58:27.229358936]
Syscalls latency statistics (usec):
Type Count Min Average Max Stdev
-----------------------------------------------------------------------------------------
Open 45 5.562 13.835 77.683 15.263
Read 109 0.316 5.774 62.569 9.277
Write 101 0.256 7.060 48.531 8.555
Sync 207 19.384 40.664 160.188 21.201

Disk latency statistics (usec):
Name Count Min Average Max Stdev
-----------------------------------------------------------------------------------------
dm-0 108 0.001 0.004 0.007 1.306


I/O request latency distribution
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: bash

lttng-iolatencyfreq /path/to/trace

::

Timerange: [2015-01-06 10:58:26.140545481, 2015-01-06 10:58:27.229358936]
Open latency distribution (usec)
###############################################################################
5.562 ███████████████████████████████████████████████████████████████████ 25
9.168 ██████████ 4
12.774 █████████████████████ 8
16.380 ████████ 3
19.986 █████ 2
23.592 0
27.198 0
30.804 0
34.410 ██ 1
38.016 0
41.623 0
45.229 0
48.835 0
52.441 0
56.047 0
59.653 0
63.259 0
66.865 0
70.471 0
74.077 █████ 2


Top system call latencies
~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: bash

lttng-iolatencytop /path/to/trace --limit=3 --minsize=2

::

Checking the trace for lost events...
Timerange: [2015-01-15 12:18:37.216484041, 2015-01-15 12:18:53.821580313]
Top open syscall latencies (usec)
Begin End Name Duration (usec) Size Proc PID Filename
[12:18:50.432950815,12:18:50.870648568] open 437697.753 N/A apache2 31517 /var/lib/php5/sess_0ifir2hangm8ggaljdphl9o5b5 (fd=13)
[12:18:52.946080165,12:18:52.946132278] open 52.113 N/A apache2 31588 /var/lib/php5/sess_mr9045p1k55vin1h0vg7rhgd63 (fd=13)
[12:18:46.800846035,12:18:46.800874916] open 28.881 N/A apache2 31591 /var/lib/php5/sess_r7c12pccfvjtas15g3j69u14h0 (fd=13)
[12:18:51.389797604,12:18:51.389824426] open 26.822 N/A apache2 31520 /var/lib/php5/sess_4sdb1rtjkhb78sabnoj8gpbl00 (fd=13)

Top read syscall latencies (usec)
Begin End Name Duration (usec) Size Proc PID Filename
[12:18:37.256073107,12:18:37.256555967] read 482.860 7.00 B bash 10237 unknown (origin not found) (fd=3)
[12:18:52.000209798,12:18:52.000252304] read 42.506 1.00 KB irqbalance 1337 /proc/interrupts (fd=3)
[12:18:37.256559439,12:18:37.256601615] read 42.176 5.00 B bash 10237 unknown (origin not found) (fd=3)
[12:18:42.000281918,12:18:42.000320016] read 38.098 1.00 KB irqbalance 1337 /proc/interrupts (fd=3)

Top write syscall latencies (usec)
Begin End Name Duration (usec) Size Proc PID Filename
[12:18:49.913241516,12:18:49.915908862] write 2667.346 95.00 B apache2 31584 /var/log/apache2/access.log (fd=8)
[12:18:37.472823631,12:18:37.472859836] writev 36.205 21.97 KB apache2 31544 unknown (origin not found) (fd=12)
[12:18:37.991578372,12:18:37.991612724] writev 34.352 21.97 KB apache2 31589 unknown (origin not found) (fd=12)
[12:18:39.547778549,12:18:39.547812515] writev 33.966 21.97 KB apache2 31584 unknown (origin not found) (fd=12)

Top sync syscall latencies (usec)
Begin End Name Duration (usec) Size Proc PID Filename
[12:18:50.162776739,12:18:51.157522361] sync 994745.622 N/A sync 22791 None (fd=None)
[12:18:37.227867532,12:18:37.232289687] sync_file_range 4422.155 N/A lttng-consumerd 19964 /home/julien/lttng-traces/analysis-20150115-120942/kernel/metadata (fd=32)
[12:18:37.238076585,12:18:37.239012027] sync_file_range 935.442 N/A lttng-consumerd 19964 /home/julien/lttng-traces/analysis-20150115-120942/kernel/metadata (fd=32)
[12:18:37.220974711,12:18:37.221647124] sync_file_range 672.413 N/A lttng-consumerd 19964 /home/julien/lttng-traces/analysis-20150115-120942/kernel/metadata (fd=32)


I/O operations log
~~~~~~~~~~~~~~~~~~

.. code-block:: bash

lttng-iolog /path/to/trace

::

[10:58:26.221618530,10:58:26.221620659] write 2.129 8.00 B /usr/bin/x-term 11793 anon_inode:[eventfd] (fd=5)
[10:58:26.221623609,10:58:26.221628055] read 4.446 50.00 B /usr/bin/x-term 11793 /dev/ptmx (fd=24)
[10:58:26.221638929,10:58:26.221640008] write 1.079 8.00 B /usr/bin/x-term 11793 anon_inode:[eventfd] (fd=5)
[10:58:26.221676232,10:58:26.221677385] read 1.153 8.00 B /usr/bin/x-term 11793 anon_inode:[eventfd] (fd=5)
[10:58:26.223401804,10:58:26.223411683] open 9.879 N/A sleep 12420 /etc/ld.so.cache (fd=3)
[10:58:26.223448060,10:58:26.223455577] open 7.517 N/A sleep 12420 /lib/x86_64-linux-gnu/libc.so.6 (fd=3)
[10:58:26.223456522,10:58:26.223458898] read 2.376 832.00 B sleep 12420 /lib/x86_64-linux-gnu/libc.so.6 (fd=3)
[10:58:26.223918068,10:58:26.223929316] open 11.248 N/A sleep 12420 (fd=3)
[10:58:26.231881565,10:58:26.231895970] writev 14.405 16.00 B /usr/bin/x-term 11793 socket:[45650] (fd=4)
[10:58:26.231979636,10:58:26.231988446] recvmsg 8.810 16.00 B Xorg 1827 socket:[47480] (fd=38)


I/O usage top
~~~~~~~~~~~~~

.. code-block:: bash

lttng-iousagetop /path/to/trace

::

Timerange: [2014-10-07 16:36:00.733214969, 2014-10-07 16:36:18.804584183]
Per-process I/O Read
###############################################################################
██████████████████████████████████████████████████ 16.00 MB lttng-consumerd (2619) 0 B file 4.00 B net 16.00 MB unknown
█████ 1.72 MB lttng-consumerd (2619) 0 B file 0 B net 1.72 MB unknown
█ 398.13 KB postgres (4219) 121.05 KB file 277.07 KB net 8.00 B unknown
256.09 KB postgres (1348) 0 B file 255.97 KB net 117.00 B unknown
204.81 KB postgres (4218) 204.81 KB file 0 B net 0 B unknown
123.77 KB postgres (4220) 117.50 KB file 6.26 KB net 8.00 B unknown
Per-process I/O Write
###############################################################################
██████████████████████████████████████████████████ 16.00 MB lttng-consumerd (2619) 0 B file 8.00 MB net 8.00 MB unknown
██████ 2.20 MB postgres (4219) 2.00 MB file 202.23 KB net 0 B unknown
█████ 1.73 MB lttng-consumerd (2619) 0 B file 887.73 KB net 882.58 KB unknown
██ 726.33 KB postgres (1165) 8.00 KB file 6.33 KB net 712.00 KB unknown
158.69 KB postgres (1168) 158.69 KB file 0 B net 0 B unknown
80.66 KB postgres (1348) 0 B file 80.66 KB net 0 B unknown
Files Read
###############################################################################
██████████████████████████████████████████████████ 8.00 MB anon_inode:[lttng_stream] (lttng-consumerd) 'fd 32 in lttng-consumerd (2619)'
█████ 834.41 KB base/16384/pg_internal.init 'fd 7 in postgres (4219)', 'fd 7 in postgres (4220)', 'fd 7 in postgres (4221)', 'fd 7 in postgres (4222)', 'fd 7 in postgres (4223)', 'fd 7 in postgres (4224)', 'fd 7 in postgres (4225)', 'fd 7 in postgres (4226)'
█ 256.09 KB socket:[8893] (postgres) 'fd 9 in postgres (1348)'
█ 174.69 KB pg_stat_tmp/pgstat.stat 'fd 9 in postgres (4218)', 'fd 9 in postgres (1167)'
109.48 KB global/pg_internal.init 'fd 7 in postgres (4218)', 'fd 7 in postgres (4219)', 'fd 7 in postgres (4220)', 'fd 7 in postgres (4221)', 'fd 7 in postgres (4222)', 'fd 7 in postgres (4223)', 'fd 7 in postgres (4224)', 'fd 7 in postgres (4225)', 'fd 7 in postgres (4226)'
104.30 KB base/11951/pg_internal.init 'fd 7 in postgres (4218)'
12.85 KB socket (lttng-sessiond) 'fd 30 in lttng-sessiond (384)'
4.50 KB global/pg_filenode.map 'fd 7 in postgres (4218)', 'fd 7 in postgres (4219)', 'fd 7 in postgres (4220)', 'fd 7 in postgres (4221)', 'fd 7 in postgres (4222)', 'fd 7 in postgres (4223)', 'fd 7 in postgres (4224)', 'fd 7 in postgres (4225)', 'fd 7 in postgres (4226)'
4.16 KB socket (postgres) 'fd 9 in postgres (4226)'
4.00 KB /proc/interrupts 'fd 3 in irqbalance (1104)'
Files Write
###############################################################################
██████████████████████████████████████████████████ 8.00 MB socket:[56371] (lttng-consumerd) 'fd 30 in lttng-consumerd (2619)'
█████████████████████████████████████████████████ 8.00 MB pipe:[53306] (lttng-consumerd) 'fd 12 in lttng-consumerd (2619)'
██████████ 1.76 MB pg_xlog/00000001000000000000000B 'fd 31 in postgres (4219)'
█████ 887.82 KB socket:[56369] (lttng-consumerd) 'fd 26 in lttng-consumerd (2619)'
█████ 882.58 KB pipe:[53309] (lttng-consumerd) 'fd 18 in lttng-consumerd (2619)'
160.00 KB /var/lib/postgresql/9.1/main/base/16384/16602 'fd 14 in postgres (1165)'
158.69 KB pg_stat_tmp/pgstat.tmp 'fd 3 in postgres (1168)'
144.00 KB /var/lib/postgresql/9.1/main/base/16384/16613 'fd 12 in postgres (1165)'
88.00 KB /var/lib/postgresql/9.1/main/base/16384/16609 'fd 11 in postgres (1165)'
78.28 KB socket:[8893] (postgres) 'fd 9 in postgres (1348)'
Block I/O Read
###############################################################################
Block I/O Write
###############################################################################
██████████████████████████████████████████████████ 1.76 MB postgres (pid=4219)
████ 160.00 KB postgres (pid=1168)
██ 100.00 KB kworker/u8:0 (pid=1540)
██ 96.00 KB jbd2/vda1-8 (pid=257)
█ 40.00 KB postgres (pid=1166)
8.00 KB kworker/u9:0 (pid=4197)
4.00 KB kworker/u9:2 (pid=1381)
Disk nr_sector
###############################################################################
███████████████████████████████████████████████████████████████████ 4416.00 sectors vda1
Disk nr_requests
###############################################################################
████████████████████████████████████████████████████████████████████ 177.00 requests vda1
Disk request time/sector
###############################################################################
██████████████████████████████████████████████████████████████████ 0.01 ms vda1
Network recv_bytes
###############################################################################
███████████████████████████████████████████████████████ 739.50 KB eth0
█████ 80.27 KB lo
Network sent_bytes
###############################################################################
████████████████████████████████████████████████████████ 9.36 MB eth0


System calls
--------

Per-TID and global system call statistics
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: bash

lttng-syscallstats /path/to/trace

::

Timerange: [2015-01-15 12:18:37.216484041, 2015-01-15 12:18:53.821580313]
Per-TID syscalls statistics (usec)
find (22785) Count Min Average Max Stdev Return values
- getdents 14240 0.380 364.301 43372.450 1629.390 {'success': 14240}
- close 14236 0.233 0.506 4.932 0.217 {'success': 14236}
- fchdir 14231 0.252 0.407 5.769 0.117 {'success': 14231}
- open 7123 0.779 2.321 12.697 0.936 {'success': 7119, 'ENOENT': 4}
- newfstatat 7118 1.457 143.562 28103.532 1410.281 {'success': 7118}
- openat 7118 1.525 2.411 9.107 0.771 {'success': 7118}
- newfstat 7117 0.272 0.654 8.707 0.248 {'success': 7117}
- write 573 0.298 0.715 8.584 0.391 {'success': 573}
- brk 27 0.615 5.768 30.792 7.830 {'success': 27}
- rt_sigaction 22 0.227 0.283 0.589 0.098 {'success': 22}
- mmap 12 1.116 2.116 3.597 0.762 {'success': 12}
- mprotect 6 1.185 2.235 3.923 1.148 {'success': 6}
- read 5 0.925 2.101 6.300 2.351 {'success': 5}
- ioctl 4 0.342 1.151 2.280 0.873 {'success': 2, 'ENOTTY': 2}
- access 4 1.166 2.530 4.202 1.527 {'ENOENT': 4}
- rt_sigprocmask 3 0.325 0.570 0.979 0.357 {'success': 3}
- dup2 2 0.250 0.562 0.874 ? {'success': 2}
- munmap 2 3.006 5.399 7.792 ? {'success': 2}
- execve 1 7277.974 7277.974 7277.974 ? {'success': 1}
- setpgid 1 0.945 0.945 0.945 ? {'success': 1}
- fcntl 1 ? 0.000 0.000 ? {}
- newuname 1 1.240 1.240 1.240 ? {'success': 1}
Total: 71847
-----------------------------------------------------------------------------------------------------------------
apache2 (31517) Count Min Average Max Stdev Return values
- fcntl 192 ? 0.000 0.000 ? {}
- newfstat 156 0.237 0.484 1.102 0.222 {'success': 156}
- read 144 0.307 1.602 16.307 1.698 {'success': 117, 'EAGAIN': 27}
- access 96 0.705 1.580 3.364 0.670 {'success': 12, 'ENOENT': 84}
- newlstat 84 0.459 0.738 1.456 0.186 {'success': 63, 'ENOENT': 21}
- newstat 74 0.735 2.266 11.212 1.772 {'success': 50, 'ENOENT': 24}
- lseek 72 0.317 0.522 0.915 0.112 {'success': 72}
- close 39 0.471 0.615 0.867 0.069 {'success': 39}
- open 36 2.219 12162.689 437697.753 72948.868 {'success': 36}
- getcwd 28 0.287 0.701 1.331 0.277 {'success': 28}
- poll 27 1.080 1139.669 2851.163 856.723 {'success': 27}
- times 24 0.765 0.956 1.327 0.107 {'success': 24}
- setitimer 24 0.499 5.848 16.668 4.041 {'success': 24}
- write 24 5.467 6.784 16.827 2.459 {'success': 24}
- writev 24 10.241 17.645 29.817 5.116 {'success': 24}
- mmap 15 3.060 3.482 4.406 0.317 {'success': 15}
- munmap 15 2.944 3.502 4.154 0.427 {'success': 15}
- brk 12 0.738 4.579 13.795 4.437 {'success': 12}
- chdir 12 0.989 1.600 2.353 0.385 {'success': 12}
- flock 6 0.906 1.282 2.043 0.423 {'success': 6}
- rt_sigaction 6 0.530 0.725 1.123 0.217 {'success': 6}
- pwrite64 6 1.262 1.430 1.692 0.143 {'success': 6}
- rt_sigprocmask 6 0.539 0.650 0.976 0.162 {'success': 6}
- shutdown 3 7.323 8.487 10.281 1.576 {'success': 3}
- getsockname 3 1.015 1.228 1.585 0.311 {'success': 3}
- accept4 3 5174453.611 3450157.282 5176018.235 ? {'success': 2}
Total: 1131


Interrupts
----------

Hardware and software interrupt statistics
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: bash

lttng-irqstats /path/to/trace

::

Timerange: [2014-03-11 16:05:41.314824752, 2014-03-11 16:05:45.041994298]
Hard IRQ Duration (us)
count min avg max stdev
----------------------------------------------------------------------------------|
1: <i8042> 30 10.901 45.500 64.510 18.447 |
42: <ahci> 259 3.203 7.863 21.426 3.183 |
43: <eth0> 2 3.859 3.976 4.093 0.165 |
44: <iwlwifi> 92 0.300 3.995 6.542 2.181 |

Soft IRQ Duration (us) Raise latency (us)
count min avg max stdev | count min avg max stdev
----------------------------------------------------------------------------------|------------------------------------------------------------
1: <TIMER_SOFTIRQ> 495 0.202 21.058 51.060 11.047 | 53 2.141 11.217 20.005 7.233
3: <NET_RX_SOFTIRQ> 14 0.133 9.177 32.774 10.483 | 14 0.763 3.703 10.902 3.448
4: <BLOCK_SOFTIRQ> 257 5.981 29.064 125.862 15.891 | 257 0.891 3.104 15.054 2.046
6: <TASKLET_SOFTIRQ> 26 0.309 1.198 1.748 0.329 | 26 9.636 39.222 51.430 11.246
7: <SCHED_SOFTIRQ> 299 1.185 14.768 90.465 15.992 | 298 1.286 31.387 61.700 11.866
9: <RCU_SOFTIRQ> 338 0.592 3.387 13.745 1.356 | 147 2.480 29.299 64.453 14.286


Interrupt handler duration frequency distribution
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: bash

lttng-irqfreq --timerange=[16:05:42,16:05:45] --irq=44 --stats /path/to/trace

::

Timerange: [2014-03-11 16:05:42.042034570, 2014-03-11 16:05:44.998914297]
Hard IRQ Duration (us)
count min avg max stdev
----------------------------------------------------------------------------------|
44: <iwlwifi> 72 0.300 4.018 6.542 2.164 |
Frequency distribution iwlwifi (44)
###############################################################################
0.300 █████ 1.00
0.612 ██████████████████████████████████████████████████████████████ 12.00
0.924 ████████████████████ 4.00
1.236 ██████████ 2.00
1.548 0.00
1.861 █████ 1.00
2.173 0.00
2.485 █████ 1.00
2.797 ██████████████████████████ 5.00
3.109 █████ 1.00
3.421 ███████████████ 3.00
3.733 0.00
4.045 █████ 1.00
4.357 █████ 1.00
4.669 ██████████ 2.00
4.981 ██████████ 2.00
5.294 █████████████████████████████████████████ 8.00
5.606 ████████████████████████████████████████████████████████████████████ 13.00
5.918 ██████████████████████████████████████████████████████████████ 12.00
6.230 ███████████████ 3.00


Community
=========

LTTng analyses is part of the `LTTng <http://lttng.org/>`_ project
and shares its community.

We hope you have fun trying this project and please remember it is a
work in progress; feedback, bug reports and improvement ideas are always
welcome!

.. list-table:: LTTng analyses project's communication channels
:header-rows: 1

* - Item
- Location
- Notes
* - Mailing list
- `lttng-dev <https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev>`_
(``[e-mail]``)
- Preferably, use the ``[lttng-analyses]`` subject prefix
* - IRC
- ``#lttng`` on the OFTC network
-
* - Code contribution
- Create a new GitHub
`pull request <https://github.com/lttng/lttng-analyses/pulls>`_
-
* - Bug reporting
- Create a new GitHub
`issue <https://github.com/lttng/lttng-analyses/issues/new>`_
-
* - Continuous integration
- `lttng-analyses_master_build item
<https://ci.lttng.org/job/lttng-analyses_master_build/>`_ on
LTTng's CI and `lttng/lttng-analyses project
<https://travis-ci.org/lttng/lttng-analyses>`_
on Travis CI
-
* - Blog
- The `LTTng blog <http://lttng.org/blog/>`_ contains some posts
about LTTng analyses
-