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<title>Snapshot algorithm</title>
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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Snapshot algorithm</span></span>
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<p>A <b>snapshot algorithm</b> is used to create a consistent snapshot of the global state of a <a href="Distributed_system" class="mw-redirect" title="Distributed system">distributed system</a>.<sup id="cite_ref-Garg2002_1-0" class="reference"><a href="#cite_note-Garg2002-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> These algorithms are not practically possible, due to the lack of both a globally shared memory and a lack of a global clock.
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<div class="mw-heading mw-heading2"><h2 id="Example">Example</h2></div>
<p>Several computers work together in a distributed system. Each of them represents a bank account holding a certain amount of money. The participants can transfer money between their accounts by exchanging the messages.
</p><p>To calculate the overall balance, just requesting the balance of each participant can lead to an incorrect result, as different accounts might be recorded before or after any transfers in progress. But a snapshot algorithm would avoid this as it makes sure to record the whole state in a point in time.
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<div class="mw-heading mw-heading2"><h2 id="Algorithms">Algorithms</h2></div>
<ul><li><a href="Chandy%E2%80%93Lamport_algorithm" title="Chandy–Lamport algorithm">Chandy–Lamport algorithm</a></li>
<li>Lai–Yang algorithm</li>
<li>Spezialetti–Kearns algorithm</li>
<li>Mattern's algorithm</li></ul>
<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>
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</style><cite id="CITEREFVijay_K._Garg2002" class="citation book cs1">Vijay K. Garg (23 May 2002). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=NlVBtVPeR0QC&dq=%22Snapshot+algorithm%22&pg=PA121"><i>Elements of Distributed Computing</i></a>. John Wiley & Sons. p. 121. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-0-471-03600-5</bdi>.</cite></span>
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This article is issued from <a class="external text" title="Last edited on 2025-02-05" href="https://en.wikipedia.org/wiki/?title=Snapshot_algorithm&oldid=1274164658">Wikipedia</a>. The text is available under <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">Creative Commons Attribution-Share Alike 4.0</a> unless otherwise noted. Additional terms may apply for the media files.
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