1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
|
DAMO: Data Access Monitoring Operator
=====================================
`damo` is a user space tool for [DAMON](https://damonitor.github.io). Using
this, you can monitor the data access patterns of your system or workloads and
make data access-aware memory management optimizations.
Demo Video
==========
Please click the below thumbnail to show the short demo video.
[](
http://www.youtube.com/watch?v=l63eqbVBZRY
"DAMON: a demo for the Kernel Summit 2020")
Getting Started
===============
[](https://repology.org/project/damo/versions)
Follow below instructions and commands to monitor and visualize the access
pattern of your workload.
$ # ensure DAMON is enabled on your kernel
$ # install damo from PyPI, or use your distribution's package manager
$ sudo pip3 install damo
$ sudo damo show $(pidof <your workload>)
$ sudo damo record $(pidof <your workload>)
$ sudo damo report heats --heatmap stdout --stdout_heatmap_color emotion
The second and last commands will show the access pattern of your workload,
like below:
FAQs
====
How can I ensure DAMON is enabled on my kernel?
-----------------------------------------------
Please refer to 'Install'
[section](https://sjp38.github.io/post/damon/#install) of the project webpage.
Where can I get more detailed usage?
------------------------------------
The below sections provide quick introductions for `damo`'s major features.
For more detailed usage, please refer to [USAGE.md](USAGE.md) file.
What does the version numbers mean?
-----------------------------------
Nothing at all but indicate which version is more fresh. A higher version
number means it is more recently released.
Will `pip3 install damo` install the latest version of `damo`?
--------------------------------------------------------------
It will install the latest _stable_ version of `damo`. If you want, you can
also install less stable but more fresh `damo` from source code. For that,
fetch the `next` branch of the source tree and use `damo` executable file in
the tree.
$ git clone https://github.com/awslabs/damo -b next
How can I participate in the development of `damo`?
---------------------------------------------------
Please refer to
[CONTRIBUTING](https://github.com/awslabs/damo/blob/next/CONTRIBUTING) file.
Why some features are not documented on [USAGE.md](USAGE.md) file?
------------------------------------------------------------------
Because those are not yet stabilized. In other words, such features are in
their experimental stages, and therefore could be deprecated and removed
without notice and grace periods. The documented features could also be
deprecated, but those will provide some notifications and grace periods. If
there are some features you're relying on but not documented, please
[report](REPORTING.md) your usecase to the community.
How can I know deprecation schedule and alternatives of specific features?
--------------------------------------------------------------------------
The list of features that will be, or already deprecated, the deprecation
schedule, and their alternatives are summarized in
[FEATURES_DEPRECATION_SCHEDULE.md](FEATURES_DEPRECATION_SCHEDULE.md) file.
Quick Intro for Major Features
==============================
Below are quick introductions for `damo`'s major features.
For more detailed usage, please refer to [USAGE.md](USAGE.md) file.
Snapshot Data Access Pattern
----------------------------
Below commands repeatedly get a snapshot of the access pattern of a program for
every second.
$ git clone https://github.com/sjp38/masim
$ cd masim; make; ./masim ./configs/zigzag.cfg --silent &
$ sudo damo start --target_pid $(pidof masim)
$ while :; do sudo damo show; sleep 1; done
The first two lines of the commands get an artificial memory access generator
program and run it in the background. It will repeatedly access two 100
MiB-sized memory regions one by one. You can substitute this with your real
workload.
The third line asks ``damo`` to start monitoring the access pattern of the
process. Finally, the last line retries a snapshot of the monitoring results
every second and show on terminal.
Recording Data Access Patterns
------------------------------
Below commands record memory access patterns of a program and save the
monitoring results in `damon.data` file.
$ git clone https://github.com/sjp38/masim
$ cd masim; make; ./masim ./configs/zigzag.cfg --silent &
$ sudo damo record -o damon.data $(pidof masim)
The first two lines of the commands get an artificial memory access generator
program and run it in the background. It will repeatedly access two 100
MiB-sized memory regions one by one. You can substitute this with your real
workload. The last line asks ``damo`` to record the access pattern in
``damon.data`` file.
Visualizing Recorded Patterns
-----------------------------
Below three commands visualize the recorded access patterns into three
image files.
$ damo report heats --heatmap stdout
$ damo report wss --range 0 101 1
$ damo report wss --range 0 101 1 --sortby time --plot
- ``access_pattern_heatmap.png`` will show the data access pattern in a
heatmap, which shows when (x-axis) what memory region (y-axis) is how
frequently accessed (color).
- ``wss_dist.png`` will show the distribution of the working set size.
- ``wss_chron_change.png`` will show how the working set size has
chronologically changed.
You can show the images on a web page [1]. Those made with other realistic
workloads are also available [2,3,4].
[1] https://damonitor.github.io/doc/html/latest/admin-guide/mm/damon/start.html#visualizing-recorded-patterns<br>
[2] https://damonitor.github.io/test/result/visual/latest/rec.heatmap.1.png.html<br>
[3] https://damonitor.github.io/test/result/visual/latest/rec.wss_sz.png.html<br>
[4] https://damonitor.github.io/test/result/visual/latest/rec.wss_time.png.html
Data Access Pattern Aware Memory Management
-------------------------------------------
Below command makes every memory region of size >=4K that hasn't accessed for
>=60 seconds in your workload to be swapped out. By doing this, you can make
your workload more memory efficient with only modest performance overhead.
$ sudo damo start --damos_access_rate 0 0 --damos_sz_region 4K max \
--damos_age 60s max --damos_action pageout \
<pid of your workload>
|
