Skip to content

Commit f9598ed

Browse files
A-HerzogA-Herzog
committed
Initial commit
0 parents  commit f9598ed

31 files changed

+1639
-0
lines changed

‎.gitignore‎

Lines changed: 4 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,4 @@
1+
.vscode/settings.json
2+
TinyFastSimulator-Java.jar
3+
images/Benchmark-LoadBalancer.xlsx
4+
images/Benchmark-noLoadBalancer.xlsx

‎LICENSE‎

Lines changed: 201 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,201 @@
1+
Apache License
2+
Version 2.0, January 2004
3+
http://www.apache.org/licenses/
4+
5+
TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
6+
7+
1. Definitions.
8+
9+
"License" shall mean the terms and conditions for use, reproduction,
10+
and distribution as defined by Sections 1 through 9 of this document.
11+
12+
"Licensor" shall mean the copyright owner or entity authorized by
13+
the copyright owner that is granting the License.
14+
15+
"Legal Entity" shall mean the union of the acting entity and all
16+
other entities that control, are controlled by, or are under common
17+
control with that entity. For the purposes of this definition,
18+
"control" means (i) the power, direct or indirect, to cause the
19+
direction or management of such entity, whether by contract or
20+
otherwise, or (ii) ownership of fifty percent (50%) or more of the
21+
outstanding shares, or (iii) beneficial ownership of such entity.
22+
23+
"You" (or "Your") shall mean an individual or Legal Entity
24+
exercising permissions granted by this License.
25+
26+
"Source" form shall mean the preferred form for making modifications,
27+
including but not limited to software source code, documentation
28+
source, and configuration files.
29+
30+
"Object" form shall mean any form resulting from mechanical
31+
transformation or translation of a Source form, including but
32+
not limited to compiled object code, generated documentation,
33+
and conversions to other media types.
34+
35+
"Work" shall mean the work of authorship, whether in Source or
36+
Object form, made available under the License, as indicated by a
37+
copyright notice that is included in or attached to the work
38+
(an example is provided in the Appendix below).
39+
40+
"Derivative Works" shall mean any work, whether in Source or Object
41+
form, that is based on (or derived from) the Work and for which the
42+
editorial revisions, annotations, elaborations, or other modifications
43+
represent, as a whole, an original work of authorship. For the purposes
44+
of this License, Derivative Works shall not include works that remain
45+
separable from, or merely link (or bind by name) to the interfaces of,
46+
the Work and Derivative Works thereof.
47+
48+
"Contribution" shall mean any work of authorship, including
49+
the original version of the Work and any modifications or additions
50+
to that Work or Derivative Works thereof, that is intentionally
51+
submitted to Licensor for inclusion in the Work by the copyright owner
52+
or by an individual or Legal Entity authorized to submit on behalf of
53+
the copyright owner. For the purposes of this definition, "submitted"
54+
means any form of electronic, verbal, or written communication sent
55+
to the Licensor or its representatives, including but not limited to
56+
communication on electronic mailing lists, source code control systems,
57+
and issue tracking systems that are managed by, or on behalf of, the
58+
Licensor for the purpose of discussing and improving the Work, but
59+
excluding communication that is conspicuously marked or otherwise
60+
designated in writing by the copyright owner as "Not a Contribution."
61+
62+
"Contributor" shall mean Licensor and any individual or Legal Entity
63+
on behalf of whom a Contribution has been received by Licensor and
64+
subsequently incorporated within the Work.
65+
66+
2. Grant of Copyright License. Subject to the terms and conditions of
67+
this License, each Contributor hereby grants to You a perpetual,
68+
worldwide, non-exclusive, no-charge, royalty-free, irrevocable
69+
copyright license to reproduce, prepare Derivative Works of,
70+
publicly display, publicly perform, sublicense, and distribute the
71+
Work and such Derivative Works in Source or Object form.
72+
73+
3. Grant of Patent License. Subject to the terms and conditions of
74+
this License, each Contributor hereby grants to You a perpetual,
75+
worldwide, non-exclusive, no-charge, royalty-free, irrevocable
76+
(except as stated in this section) patent license to make, have made,
77+
use, offer to sell, sell, import, and otherwise transfer the Work,
78+
where such license applies only to those patent claims licensable
79+
by such Contributor that are necessarily infringed by their
80+
Contribution(s) alone or by combination of their Contribution(s)
81+
with the Work to which such Contribution(s) was submitted. If You
82+
institute patent litigation against any entity (including a
83+
cross-claim or counterclaim in a lawsuit) alleging that the Work
84+
or a Contribution incorporated within the Work constitutes direct
85+
or contributory patent infringement, then any patent licenses
86+
granted to You under this License for that Work shall terminate
87+
as of the date such litigation is filed.
88+
89+
4. Redistribution. You may reproduce and distribute copies of the
90+
Work or Derivative Works thereof in any medium, with or without
91+
modifications, and in Source or Object form, provided that You
92+
meet the following conditions:
93+
94+
(a) You must give any other recipients of the Work or
95+
Derivative Works a copy of this License; and
96+
97+
(b) You must cause any modified files to carry prominent notices
98+
stating that You changed the files; and
99+
100+
(c) You must retain, in the Source form of any Derivative Works
101+
that You distribute, all copyright, patent, trademark, and
102+
attribution notices from the Source form of the Work,
103+
excluding those notices that do not pertain to any part of
104+
the Derivative Works; and
105+
106+
(d) If the Work includes a "NOTICE" text file as part of its
107+
distribution, then any Derivative Works that You distribute must
108+
include a readable copy of the attribution notices contained
109+
within such NOTICE file, excluding those notices that do not
110+
pertain to any part of the Derivative Works, in at least one
111+
of the following places: within a NOTICE text file distributed
112+
as part of the Derivative Works; within the Source form or
113+
documentation, if provided along with the Derivative Works; or,
114+
within a display generated by the Derivative Works, if and
115+
wherever such third-party notices normally appear. The contents
116+
of the NOTICE file are for informational purposes only and
117+
do not modify the License. You may add Your own attribution
118+
notices within Derivative Works that You distribute, alongside
119+
or as an addendum to the NOTICE text from the Work, provided
120+
that such additional attribution notices cannot be construed
121+
as modifying the License.
122+
123+
You may add Your own copyright statement to Your modifications and
124+
may provide additional or different license terms and conditions
125+
for use, reproduction, or distribution of Your modifications, or
126+
for any such Derivative Works as a whole, provided Your use,
127+
reproduction, and distribution of the Work otherwise complies with
128+
the conditions stated in this License.
129+
130+
5. Submission of Contributions. Unless You explicitly state otherwise,
131+
any Contribution intentionally submitted for inclusion in the Work
132+
by You to the Licensor shall be under the terms and conditions of
133+
this License, without any additional terms or conditions.
134+
Notwithstanding the above, nothing herein shall supersede or modify
135+
the terms of any separate license agreement you may have executed
136+
with Licensor regarding such Contributions.
137+
138+
6. Trademarks. This License does not grant permission to use the trade
139+
names, trademarks, service marks, or product names of the Licensor,
140+
except as required for reasonable and customary use in describing the
141+
origin of the Work and reproducing the content of the NOTICE file.
142+
143+
7. Disclaimer of Warranty. Unless required by applicable law or
144+
agreed to in writing, Licensor provides the Work (and each
145+
Contributor provides its Contributions) on an "AS IS" BASIS,
146+
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
147+
implied, including, without limitation, any warranties or conditions
148+
of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
149+
PARTICULAR PURPOSE. You are solely responsible for determining the
150+
appropriateness of using or redistributing the Work and assume any
151+
risks associated with Your exercise of permissions under this License.
152+
153+
8. Limitation of Liability. In no event and under no legal theory,
154+
whether in tort (including negligence), contract, or otherwise,
155+
unless required by applicable law (such as deliberate and grossly
156+
negligent acts) or agreed to in writing, shall any Contributor be
157+
liable to You for damages, including any direct, indirect, special,
158+
incidental, or consequential damages of any character arising as a
159+
result of this License or out of the use or inability to use the
160+
Work (including but not limited to damages for loss of goodwill,
161+
work stoppage, computer failure or malfunction, or any and all
162+
other commercial damages or losses), even if such Contributor
163+
has been advised of the possibility of such damages.
164+
165+
9. Accepting Warranty or Additional Liability. While redistributing
166+
the Work or Derivative Works thereof, You may choose to offer,
167+
and charge a fee for, acceptance of support, warranty, indemnity,
168+
or other liability obligations and/or rights consistent with this
169+
License. However, in accepting such obligations, You may act only
170+
on Your own behalf and on Your sole responsibility, not on behalf
171+
of any other Contributor, and only if You agree to indemnify,
172+
defend, and hold each Contributor harmless for any liability
173+
incurred by, or claims asserted against, such Contributor by reason
174+
of your accepting any such warranty or additional liability.
175+
176+
END OF TERMS AND CONDITIONS
177+
178+
APPENDIX: How to apply the Apache License to your work.
179+
180+
To apply the Apache License to your work, attach the following
181+
boilerplate notice, with the fields enclosed by brackets "[]"
182+
replaced with your own identifying information. (Don't include
183+
the brackets!) The text should be enclosed in the appropriate
184+
comment syntax for the file format. We also recommend that a
185+
file or class name and description of purpose be included on the
186+
same "printed page" as the copyright notice for easier
187+
identification within third-party archives.
188+
189+
Copyright [yyyy] [name of copyright owner]
190+
191+
Licensed under the Apache License, Version 2.0 (the "License");
192+
you may not use this file except in compliance with the License.
193+
You may obtain a copy of the License at
194+
195+
http://www.apache.org/licenses/LICENSE-2.0
196+
197+
Unless required by applicable law or agreed to in writing, software
198+
distributed under the License is distributed on an "AS IS" BASIS,
199+
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
200+
See the License for the specific language governing permissions and
201+
limitations under the License.

‎NOTICE‎

Lines changed: 4 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,4 @@
1+
Simple discrete event-oriented simulator for G/G/c models
2+
Copyright 2025 Alexander Herzog
3+
4+
Licensed under the Apache License, Version 2.0.

‎README.md‎

Lines changed: 79 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,79 @@
1+
# Simple discrete event-oriented simulator for G/G/c models (Java edition)
2+
3+
This is a very simple discrete event-oriented simulator (DES) which can simulate G/G/c models. The results are shown on the console.
4+
The statistic recording is very basic.
5+
The main purpose of the tool is not to gain new insights into queueing theory, but rather to get an upper estimate of the maximum speed a simulation tool can achieve on a given computer.
6+
7+
## Model
8+
9+
The simulator can generate pseudo-random numbers according to the exponential distribution and to the log-normal distribution.
10+
If a coefficient of variation of 1 is chosen for some parameter, the exponential distribution will be used; otherwise the log-normal distribution will be used.
11+
12+
Default values if not overwritten by command-line arguments:
13+
14+
* Mean inter-arrival time **E[I]=100**
15+
* Coefficient of variation of the inter-arrival times **CV[I]=1**
16+
* Mean service time **E[S]=80**
17+
* Coefficient of variation of the service times **CV[S]=1**
18+
* Number of operators **c=1**
19+
* Number of arrivals to be simulated **arrivals=100,000,000**
20+
* Number of threads to be used **threads=<number of available logical CPU cores>**
21+
22+
The number of arrivals is distributed equally between all used threads. The statistic results are combined at the end of the simulation process.
23+
24+
## Command-line arguments
25+
26+
The model parameters above can be altered by command-line arguments. All model parameters not being changed via command-line are kept on the default values.
27+
28+
* `EI=` mean inter-arrival times (positive floating point number)
29+
* `cvI=` coefficient of variation of the inter-arrival times (non-negative floating point number)
30+
* `ES=` mean service times (positive floating point number)
31+
* `cvS=` coefficient of variation of the service times (non-negative floating point number)
32+
* `c=` number of operators (positive integer)
33+
* `arrivals=` number of arrivals (positive integer; can be more than 4 bil.)
34+
* `threads=` number of threads to be used (positive integer)
35+
* `increase_arrivals` (no additional value) multiplies the actual number of arrivals by the number of threads
36+
* `show_times` (no additional value) shows the runtime of the individual threads
37+
* `load_balancer` (no additional value) activates load balancing between the threads
38+
39+
The `increase_arrivals` parameter is useful for benchmarking: When using this parameter the average runtime will be approximately the runtime of the specified number of arrivals in the single thread case. (So the runtimes will not become shorter when increasing the number of threads.)
40+
41+
The number of threads can be larger than the number of available logical CPU cores.
42+
43+
## Benchmarking script
44+
45+
The `TinyFastSimulator-Benchmark.sh` (no load balancer mode) and the `TinyFastSimulator-Balanced-Benchmark.sh` (load balancer mode) scripts can be used to test the performance in relation to the number of threads. The scripts are to be called with three parameters: the maximum number of threads to be used, the number of arrivals per thread and the output file. The scripts will run the simulator with one threads and the number of arrival specified; then with two threads and the double total number of arrivals etc. until the specified maximum number of threads is reached. For each simulation run one line is added to the specified output file. Each line will have three columns: the number of threads used, the runtime (in seconds) and the used RAM (in KB). To get statistical stable result a number of arrivals of 100,000,000 or higher should be used.
46+
47+
Usage example: `./TinyFastSimulator-Benchmark.sh 32 100000000 results.txt`
48+
49+
## Benchmark results
50+
51+
The following benchmarks were performed on a system with two CPU of the type AMD Epyc 7281 (Zen+ architecture, 16 physical / 32 logical cores each).
52+
53+
### No load balancer
54+
55+
![Benchmark - no load balancer - absolute performance](images/Benchmark1.png)
56+
57+
![Benchmark - no load balancer - relative performance](images/Benchmark2.png)
58+
59+
### Load balancer
60+
61+
![Benchmark - load balancer - absolute performance](images/Benchmark3.png)
62+
63+
![Benchmark - load balancer - relative performance](images/Benchmark4.png)
64+
65+
Even so the benchmark probably runs completely from the cache and hardly accesses the RAM, the SMT winnings are nevertheless very high.
66+
67+
The number of arrivals was 100,000,000 in the single thread case, 200,000,000 when using two threads etc. In this way the simulation runtime are (approximately) constant over all numbers of threads.
68+
69+
## Building
70+
71+
A `jar` file can be generated using Maven. Just go to the `tinyfastsimulator` folder and run
72+
```
73+
mvn package
74+
```
75+
The `jar` file will be generated in the `tinyfastsimulator/target` folder.
76+
77+
## Contact
78+
79+
[Alexander Herzog](https://github.com/A-Herzog)

‎SECURITY.md‎

Lines changed: 11 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,11 @@
1+
# Security Policy
2+
3+
## Supported Versions
4+
Security updates are applied only to the latest release.
5+
6+
## Reporting a Vulnerability
7+
If you have discovered a security vulnerability in this project, please report it privately. **Do not disclose it as a public issue.** This gives us time to work with you to fix the issue before public exposure, reducing the chance that the exploit will be used before a patch is released.
8+
9+
Please disclose it at our [security advisory](https://github.com/A-Herzog/TinyFastSimulator-Java/security/advisories/new).
10+
11+
This project is maintained by volunteers on a reasonable-effort basis. As such, vulnerabilities will be disclosed in a best effort base.

‎TinyFastSimulator-Balanced-Benchmark.sh‎

Lines changed: 28 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,28 @@
1+
#!/bin/bash
2+
3+
if [ ! -f "./TinyFastSimulator-Java.jar" ]
4+
then
5+
echo "Simulator program file (TinyFastSimulator-Java.jar) not found"
6+
exit 1
7+
fi
8+
9+
if [ "$1" == "" -o "$2" == "" -o "$3" == "" ]
10+
then
11+
echo "The script has to be called with three parameters:"
12+
echo "1. Maximum number of threads"
13+
echo "2. Number of arrivals (in single thread mode) to be simulated"
14+
echo "3. Output file for the results"
15+
echo "Example: ./TinyFastSimulator-Benchmark.sh 32 100000000 results.txt"
16+
exit 1
17+
fi
18+
19+
echo "Benchmarking the performance at different numbers of threads"
20+
echo "Output will be written to $3"
21+
22+
echo -e "Threads\tRuntime [sec.]\tMemory [KB]" >> $3
23+
for ((x=1;x<=$1;x++))
24+
do
25+
echo "Running simulation $x of $1"
26+
echo -en "$x\t" >> $3
27+
\time -f "%e\t%M" -o $3 -a java -jar TinyFastSimulator-Java.jar load_balancer threads=$x arrivals=$2 increase_arrivals > /dev/null
28+
done

‎TinyFastSimulator-Benchmark.sh‎

Lines changed: 28 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,28 @@
1+
#!/bin/bash
2+
3+
if [ ! -f "./TinyFastSimulator-Java.jar" ]
4+
then
5+
echo "Simulator program file (TinyFastSimulator-Java.jar) not found"
6+
exit 1
7+
fi
8+
9+
if [ "$1" == "" -o "$2" == "" -o "$3" == "" ]
10+
then
11+
echo "The script has to be called with three parameters:"
12+
echo "1. Maximum number of threads"
13+
echo "2. Number of arrivals (in single thread mode) to be simulated"
14+
echo "3. Output file for the results"
15+
echo "Example: ./TinyFastSimulator-Benchmark.sh 32 100000000 results.txt"
16+
exit 1
17+
fi
18+
19+
echo "Benchmarking the performance at different numbers of threads"
20+
echo "Output will be written to $3"
21+
22+
echo -e "Threads\tRuntime [sec.]\tMemory [KB]" >> $3
23+
for ((x=1;x<=$1;x++))
24+
do
25+
echo "Running simulation $x of $1"
26+
echo -en "$x\t" >> $3
27+
\time -f "%e\t%M" -o $3 -a java -jar TinyFastSimulator-Java.jar threads=$x arrivals=$2 increase_arrivals > /dev/null
28+
done

‎images/Benchmark1.png‎

222 KB
Loading

‎images/Benchmark2.png‎

212 KB
Loading

‎images/Benchmark3.png‎

160 KB
Loading

0 commit comments

Comments
 (0)