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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Improve data backup strategies with machine learning predictive analytics⋆</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Andrii Harasivka</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Anatolii Lupenko</string-name>
          <email>lupenkoan@gmail.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Yuri Palaniza</string-name>
          <email>palanizayb@tntu.edu.ua</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Mykhailo Fryz</string-name>
          <email>mykh.fryz@gmail.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Ternopil Ivan Puluj National Technical University</institution>
          ,
          <addr-line>56, Ruska Street, Ternopil, 46001</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>This paper investigates the application of machine learning (ML) model to predict data backup needs and optimize backup solutions in any-scale IT environment. By leveraging ML-driven predictive analytics, users and companies can enhance the efficiency and reliability of their data backup processes, increase performance, reduce costs, and minimize data loss in case incident. The paper describes a solution utilizing the RandomForestRegressor model for learning on attributes of existing files in system to predict a priority of processing backup of files and avoid data redundancy via skipping extra files. It will allow to speed up the backup process and reduce the size of the  backup. With enough training on metadata of files and filesystem behavior, the solution will help make backup software more resistant to errors, intelligent and dynamic.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;data backup</kwd>
        <kwd>machine learning</kwd>
        <kwd>software development</kwd>
        <kwd>RandomForestRegressor1</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        Data is a critical asset for companies in the digital age, who use it as the basis of all operations,
decision-making, and strategic planning [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. Data loss due to hardware failures, cyber-attacks,
or human errors can have catastrophic consequences, including financial losses, reputational
damage, and operational disruptions. Traditional data backup strategies often rely on fixed
schedules and heuristic rules, which can be inefficient and insufficiently responsive to the
dynamic nature of modern IT environments.
      </p>
      <p>
        The primary problem is the lack of adaptive, intelligent systems that can predict and
optimize data backup scope needs in real-time. Fixed backup schedules often lead to excessive
resource consumption by frequently backing up low-priority data and neglecting the needed
backup of critical, high-priority data [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Additionally, these traditional methods do not take into
account evolving data usage patterns, system loads, and emerging threats, resulting in
insufficient backup performance and potential data loss [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
      <p>
        Therefore, there is a need for a new approach that leverages new technics to perform
predictive analytics for data backup strategies. For such needs perfectly fit one of machine
learning models [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ], for example, random forest regressor. By predicting possible scenarios of
data modifications, and identifying critical entities of data, ML-driven solutions can improve the
efficiency, reliability, and cost-effectiveness of data backup strategy: processes, environments,
and schedule. This research aims to contribute to the field of developing data backup systems by
providing a novel approach for analyzing data with the use of ML.
      </p>
    </sec>
    <sec id="sec-2">
      <title>2. Literature review</title>
      <p>
        Every company that processes any data should take responsibility not only for its secure and
reliable storage but also for corresponding data backup solution. Currently, existing backup
software solutions could perform backups of separate files, folders, or volumes of data via a
straight and narrow approach by performing one or few backup schemes or its combinations
(full, incremental, differential). Full data backup means the solution will make a full copy of
source data, it offers the simplest recovery but consumes the most time and storage space.
Incremental backup - only backs up data that has changed since the last backup, saving time and
storage but requiring multiple backups for a full restore. Differential backup saves all changes
made since the last full backup, balancing time and storage between full and incremental
backups [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
      </p>
      <p>To avoid weak parts of existing backup solutions and make the system more dynamic, a new
machine-learning-driven solution should help. ML algorithms can significantly improve data
backup strategies through various approaches, optimizing both the efficiency and reliability of
the backup strategy. This allows to create more intelligent schedule of backups, ensuring that
critical data is backed up more frequently while less critical data is backed up less often. This
reduces the amount of backups, storage usage and maintains efficient storage utilization.</p>
      <p>Another area to optimize – make adaptive backup policies based on real-time monitoring of
system resources. For instance, if the ML algorithm detects increased activity in certain datasets,
it can trigger more frequent backups for those datasets temporarily. By monitoring the usage of
machine resources and their trends (e.g., bandwidth, storage, memory, central processing unit),
the ML algorithm can predict the best times for backups to ensure minimal disruption to regular
operations and efficient use of resources.</p>
      <p>
        Due to the increasing amount of data [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ], every software solution should consider applying
single or multiple options of data deduplication and compression. ML algorithm can analyze
data type or attributes and classify data, to enhance deduplication and compression techniques,
choose the best archiving mechanism, and reduce the amount of storage required. Critical data
might receive more frequent and robust backup measures, while less important data is backed
up less frequently or with fewer resources [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ].
      </p>
      <p>Additionally, ML algorithms can predict potential backup failures by analyzing system
events, logs, and metrics. This allows the backup system to take proactive measures, such as
rerunning a backup process or fixing underlying issues before a critical backup operation fails. If
a system event happens during backup, the ML algorithm can initiate a spare process of
verifying backups and checking their integrity. This ensures that backups are complete,
uncorrupted, and can be restored successfully when needed.</p>
      <p>Every company has its own policies for IT environment, including data storage, its backups
and retention periods, security of systems; so the ML algorithm can ensure that data backup
strategies comply with organizational policies and regulatory requirements by continuously
monitoring backup processes and systems to meet compliance standards.</p>
      <p>To overcome the problems of existing backup software, a new machine-learning backup
solution is proposed to solve fixed schedule and redundant data problems. For this purpose,
RandomForestRegressor model was selected. This model has the resilience to noisy data, no
need for extensive data preprocessing, ability to handle non-linear relationships which make it
perfect for performing analytics among file system entries and user behavior.</p>
    </sec>
    <sec id="sec-3">
      <title>3. Proposed solution</title>
      <p>The proposed software solution should solve the problems mentioned above - avoid redundant
files, and make the backup schedule by assigning priority for tasks. The main advantage of the
proposed solution will be a feature of predicting priority to make backup of important files
faster and speed up the backup process.</p>
      <p>For that purpose will be enough of a simple console application. It should consist of a few
modules: main – which is the entry point of a system; BackupScheduler – a service to fire
backup activities (directly or via timer), BackupExecutor – a main component that performs
backup activity, FileChangeStatisticsHandler – a module for tracking of file system changes.
The system structure diagram is shown in figure 1.</p>
      <p>Development of such a solution will require a Python interpreter installed, Pip configured,
Pandas and Scikit-learn, NumPy modules imported, text editor on Windows/Linux/MacOS
machine. Additional features, like filesystem access were imported from os, shutil, and glob.</p>
      <p>To be able to train a RandomForestRegressor model there will be a need for a large set of
data, which could be any directory with different types of files, for the proposed solution it will
be %userprofile%\Documents.</p>
      <p>In the first step, need to define the criteria of files and how they should be preprocessed - the
model should build relations to predict “backup_priority” and “backup_type” of file.
Preprocessing allows data to make it suitable for training machine learning models. Model
training will be performed by such attributes as: “size”, “last_modified”, “created“, “is_system”,
“is_hidden”, “is_readonly”. Target attributes that should be predicted are: “backup_priority” and
“backup_type”. Both groups of attributes should be defined, so a model could split data into
logical relations between source and result and make sufficient decisions in the future.</p>
      <p>The process of model training is iterative: which means the developer should pass incoming
variables and review model prediction results in every iteration – if the prediction value does
not fall into the expected range – adjust incoming values and repeat. All coefficients should be
adjusted due to the exact filesystem and case. It could be implemented by simple conditions – for
example, if the file was created less than a minute ago – increment priority by 10, or if file size is
less than file system block size (for Microsoft Windows its 4kb) – then it could be more efficient
to copy it rather then archive. The algorithm of estimating “backup_priority” is displayed in
figure 2 (as there are many criteria to estimate – most of them hidden in function).</p>
      <p>Start of the software will be from the Main module. It's an entry point of a console program,
which takes arguments: training data path, backup source path, backup target path. Main
initiate analyzing of scanning files in the training data path and start RandomForestRegressor
model training. It includes the following steps:
1. splitting data into training and actual (made by function “train_test_split” from
“sklearn.model_selection”)
2. creating multi-target regressor – to be able to predict multiple variables with the
same model (class “MultiOutputRegressor”)
3. fit model to train data (function “fit”).</p>
      <p>BackupScheduler has no logic except repeated timer and queue which allows to schedule,
postpone, and send backup tasks to BackupExecutor. Additionally, it utilizes CPU and RAM
metrics of OS to avoid making backup task when OS under load.</p>
      <p>FileChangeStatisticsHandler is a handler derived from “FileSystemEventHandler” to be able
to track file system modifications. It implements “on_modified” method which fired on any
modification of a file. Unfortunately, it fired even if file metadata changed (in Microsoft
Windows 10 environment). So, to avoid extra changes of “last_access” attribute of a file, handler
should also calculate, save, and compare MD5 hash of file, it can be made by “md5” function of
“hashlib”. Additionally, to have full history of file changes its save dictionary of dates by file into
a temporary file.</p>
      <p>BackupExecutor uses trained model to predict the backup priority of file(s) by its metadata.
“Predict” function return array of results, it our case it is 2 target values due to 2 target attributes
”backup_priority” and “backup_type”. Based on the prediction - a corresponding backup action
will be made: either ignore the file (e.g. ”backup_priority” have 0 importance for backup), copy
the file (e.g. it’s a small file), or zip file (it's a large file).</p>
    </sec>
    <sec id="sec-4">
      <title>4. Evaluation of results</title>
      <p>Evaluation of data backup solutions involves comparing different factors to determine which
option best meets specific needs. Data backup solutions should consider the type and volume of
data, the speed and frequency of backups, redundancy, storage use and reliability. Need to have
a set of metrics to evaluate and compare the performance and redundancy of existing and new
backup solutions:



</p>
      <p>
        Compressed size: size of compressed backup files [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ], measured in bytes.
      </p>
      <p>Space saving: the reduction in the size of original data relative to the uncompressed data
size, calculated by the formula (1).</p>
      <p>Time spent: The duration of the backup process, measured in s.</p>
      <p>Redundancy: The size of extra files that are included in the backup (temporary files made
by other software, operating system files, non-accessible files) - redundant and
irrelevant files, calculated by formula (2).</p>
      <p>Space saving , %=1−Compressed ¿ ¿ Uncompressed ¿ ¿ 100 , ¿ ¿
Redundancy , %=1− Redundant files ¿ ¿ Compressed ¿ ¿ 100 , ¿ ¿
(1)
(2)</p>
      <p>Attributes "Space saving" and "Redundancy" are the key indicators of the quality of a backup
solution. With ideal software, the "Space saving" should be positive, and as large as possible, and
the "redundancy value" should lead to 0.</p>
      <p>Software solutions perform backup to the same disk as source data to keep hardware
input/output delay as small as possible. The technical specification of the test machine is shown
in table 1.</p>
      <p>Uncompressed
size, bytes
250 774 175
250 774 175
250 774 175
250 774 175
250 774 175
250 774 175</p>
      <p>Time
spent,
s
8
90
8
37,55
2,60
5,33</p>
      <p>Compressed
size, bytes
245 683 200
251 187 200
179 387 221
240 815 723
241 507 281
241 486 408</p>
      <p>Space
saving,</p>
      <p>%
2.03
-0.16
28.47
3.97
3.7
3.7</p>
      <p>Redund
ant files
size,
bytes
11 702
11 702
11 702
11 702
11 702
0</p>
      <p>As we can see from the results in table 2 most software performs a backup of redundant files
(column “Redundancy files size” - 11 702 bytes), while the proposed solution has 0% redundancy,
which is the perfect case among backup software. Also, proposed solution has a high level of
“space saving”: 3,7%, while the biggest level is achieved by Duplicati: 28,47%. Additionally, the
test for the proposed solution took only 5,33 seconds which is second place after the best - 2,60
seconds by WinZip.</p>
      <p>The results of the second test displayed in table 3, confirms that the proposed solution has
the smallest value of “redundant files size”: 2 429 307bytes (0,04% redundancy), which is ~4 times
less than competitors. The value of “space saving” of the proposed solution is the biggest among
competitive software - 2,29%, but it took 91,483 seconds.</p>
      <p>So, the evaluation of the result of testing the proposed solution shows good conclusions: the
smallest size of redundant files, a high value of “Space saving” and a low amount of “Time spent”
means that the RandomForestRegressor model successfully fit for our needs. Applying this
machine learning model will significantly improve the performance of backup software – so
end-customers will see that backup software will check their latest files first and reduce time
spent on backup.</p>
    </sec>
    <sec id="sec-5">
      <title>5. Conclusion and future work</title>
      <p>The paper provides insights into the potential of ML-driven predictive analytics solutions to
improve data backup strategies, ultimately contributing to more robust, efficient, and adaptive
systems. By integrating these ML approaches, software companies can develop more
sophisticated and responsive data backup solutions to improve existing IT environments.</p>
      <p>One of the key areas for improvement could be the use of more advanced multi-target
regression models. Specifically, we plan to employ a more complex multi-target XGBoost
regressor (in One-Model-Per-Target or Vector Leaf mode) for predicting the target attributes
"backup_priority" and "backup_type". One of its primary benefits is its efficiency and scalability,
making it suitable for both small and large-scale datasets.</p>
      <p>
        Future steps for the research could be: using data sets with a bigger amount of different files
to teach and train a model, including immunosensors [
        <xref ref-type="bibr" rid="ref10 ref11 ref12 ref13">10-13</xref>
        ], cyber-physical [14-17] and cardio
diagnostic [18-19] systems, fitting and adjusting the model due to a higher amount of attributes:
filesystem permissions, the file owner and monitoring system activity during processing
backup; implementing a multithreading execution of backup; deploying the application as a
separate application for target operating systems.
Systems Analysis (Vol. 55, Issue 4, pp. 625–637). Springer Science and Business Media LLC.
https://doi.org/10.1007/s10559-019-00171-2
[14] Martsenyuk, V., Klos-Witkowska, A., Sverstiuk, A., Bahrii-Zaiats O., Bernas, M., Witos, K.
      </p>
      <p>Intelligent big data system based on scientific machine learning of cyber-physical systems
of medical and biological processes. CEUR Workshop Proceedings, 2021, 2864, pp. 34–48.
[15] Martsenyuk, V., Sverstiuk, A., Bahrii-Zaiats, O., Kłos-Witkowska, A. Qualitative and
Quantitative Comparative Analysis of Results of Numerical Simulation of Cyber-Physical
Biosensor Systems. CEUR Workshop Proceedings, 2022, 3309, pp. 134–149.
[16] Martsenyuk V., Sverstiuk A., Klos-Witkowska L., Nataliia K., Bagriy-Zayats O., Zubenko I.</p>
      <p>Numerical analysis of results simulation of cyber-physical biosensor systems (2019) CEUR
Workshop Proceedings, 2516, pp. 149 – 164.
[17] Martsenyuk V., Sverstiuk A., Bahrii-Zaiats O., Kłos-Witkowska A. Qualitative and
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