| 1 | <html xmlns:n="http://nevow.com/ns/nevow/0.1"> |
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| 2 | <head> |
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| 3 | <title>Tahoe-LAFS - Reliability Tool</title> |
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| 4 | <link href="/tahoe.css" rel="stylesheet" type="text/css"/> |
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| 5 | <link href="/icon.png" rel="shortcut icon" /> |
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| 6 | <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> |
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| 7 | </head> |
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| 8 | <body> |
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| 9 | |
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| 10 | <h1>Tahoe-LAFS Reliability Tool</h1> |
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| 11 | |
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| 12 | <p>Given certain assumptions, this page calculates probability of share loss |
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| 13 | over time, to help make informed decisions about how much redundancy and |
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| 14 | repair bandwidth to configure on a Tahoe-LAFS grid.</p> |
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| 15 | |
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| 16 | <div n:render="forms" /> |
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| 17 | |
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| 18 | <h2>Simulation Results</h2> |
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| 19 | |
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| 20 | <p>At the end of the report span (elapsed time <span n:render="report_span" |
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| 21 | />), the simulated file had the following properties:</p> |
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| 22 | |
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| 23 | <ul> |
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| 24 | <li>Probability of loss (no maintenance): |
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| 25 | <span n:render="P_loss_unmaintained"/></li> |
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| 26 | <li>Probability of loss (with maintenance): |
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| 27 | <span n:render="P_loss_maintained"/></li> |
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| 28 | <li>Average repair frequency: |
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| 29 | once every <span n:render="P_repair_rate"/> secs</li> |
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| 30 | <li>Average shares generated per repair: |
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| 31 | <span n:render="P_repair_shares"/></li> |
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| 32 | </ul> |
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| 33 | |
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| 34 | <p>This table shows how the following properties change over time:</p> |
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| 35 | <ul> |
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| 36 | <li>P_repair: the chance that a repair was performed in the most recent |
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| 37 | check period.</li> |
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| 38 | <li>P_dead (unmaintained): the chance that the file will be unrecoverable |
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| 39 | without periodic check+repair</li> |
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| 40 | <li>P_dead (maintained): the chance that the file will be unrecoverable even |
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| 41 | with periodic check+repair</li> |
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| 42 | </ul> |
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| 43 | |
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| 44 | <div> |
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| 45 | <table n:render="sequence" n:data="simulation_table"> |
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| 46 | <tr n:pattern="header"> |
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| 47 | <td>t</td> |
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| 48 | <td>P_repair</td> |
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| 49 | <td>P_dead (unmaintained)</td> |
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| 50 | <td>P_dead (maintained)</td> |
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| 51 | </tr> |
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| 52 | <tr n:pattern="item" n:render="simulation_row"> |
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| 53 | <td><n:slot name="t"/></td> |
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| 54 | <td><n:slot name="P_repair"/></td> |
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| 55 | <td><n:slot name="P_dead_unmaintained"/></td> |
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| 56 | <td><n:slot name="P_dead_maintained"/></td> |
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| 57 | </tr> |
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| 58 | <tr n:pattern="empty"><td>no simulation data!</td></tr> |
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| 59 | </table> |
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| 60 | </div> |
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| 61 | |
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| 62 | </body> |
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| 63 | </html> |
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