snapraid/beta/design.html

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                SnapRAID
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                    <li><a href="index" >Home</a></li>
                    <li><a href="ui" >UI & Daemon</a></li>
                    <li><a href="howitworks" >How it Works</a></li>
                    <li><a href="design" class="active">Design</a></li>
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            <h1 style="margin-bottom: 1rem;">Design Philosophy</h1>
            <blockquote style="font-size: 1.5rem; color: var(--text-accent); font-style: italic; margin: 0; padding: 0; border: none; font-family: serif;">
                Simplicity is prerequisite for reliability
            </blockquote>
            <cite style="display: block; margin-top: 1rem; font-size: 1rem; color: var(--text-secondary); font-style: normal;">
                <a href="http://en.wikipedia.org/wiki/Edsger_W._Dijkstra" style="color: var(--text-secondary); text-decoration: underline;">Edsger W. Dijkstra</a>
            </cite>
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                <strong style="color: var(--text-primary);">SnapRAID</strong> was created following the <a href="http://en.wikipedia.org/wiki/Unix_philosophy">Unix philosophy</a>:
                <em>Write programs that do one thing and do it well</em>.
            </p>
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                <h3>Reliability</h3>
            <p>
                The first design principle was <strong style="color: var(--text-primary);">reliability</strong>.
                The result is a simple architecture and an easy to understand implementation.
            </p>
                <p>
                    Extensive and automated tests with the runtime checker <a href="http://valgrind.org/">Valgrind</a>
                    and with the <a href="https://github.com/google/sanitizers">Google Sanitizers</a>
                    are done to ensure the correctness of the final application.
                    The test has a <a href="/cov/">code coverage of over 90%</a>, measured with <a href="https://github.com/linux-test-project/lcov">lcov</a>.
                </p>
                <p>
                    SnapRAID is also verified with the
                    <a href="https://scan.coverity.com/projects/snapraid">Coverity Scan</a>
                    and <a href="http://clang-analyzer.llvm.org/">clang</a> static analyzers,
                    and with the <a href="http://lcamtuf.coredump.cx/afl/">American Fuzzy Lop</a> fuzzy tester.
                </p>
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                <h3>Robustness</h3>
                <p>
                    The second design principle was <strong style="color: var(--text-primary);">robustness</strong>.
                    It supports any kind of problem. Even on kernel panics, power-downs
                    or any other hard failure at runtime, your redundancy data is in safe hands.
                </p>
                <p>
                    It uses all the possible storage techniques to ensure to always keep consistent
                    redundancy even after critical interruptions.
                </p>
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                <h3>Efficiency</h3>
                <p>
                    The third design principle was <strong style="color: var(--text-primary);">efficiency</strong>.
                    It's a native C application highly optimized to ensure maximum throughput of your disk array.
                </p>
                <p>
                    Integrity checks use the highly efficient <a href="http://code.google.com/p/smhasher/">murmur3</a>
                    and <a href="http://burtleburtle.net/bob/hash/spooky.html">SpookyHash</a> hashes at 128 bits.
                </p>
                <p>
                    Redundancy computations use a custom <a href="https://github.com/amadvance/snapraid/tree/master/raid">RAID library</a>
                    (based on Linux Kernel RAID) supporting up to six parity levels.
                    Internal structures use <a href="http://www.tommyds.it/">TommyDS</a>.
                </p>
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                <h3>SnapRAID</h3>
                <p>Copyright &copy; 2026 Andrea Mazzoleni</p>
                <p class="license">Distributed under GPL v3 License</p>
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                <h4>Community</h4>
                <ul>
                    <li><a href="https://www.reddit.com/r/Snapraid/">Reddit r/snapraid</a></li>
                    <li><a href="https://sourceforge.net/p/snapraid/discussion/1677233/">SourceForge Forum</a></li>
                    <li><a href="https://github.com/amadvance/snapraid/">GitHub SnapRAID CLI</a></li>
                    <li><a href="https://github.com/amadvance/snapraid-daemon/">GitHub SnapRAID Daemon</a></li>
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