<html xmlns:n="http://nevow.com/ns/nevow/0.1"> <head> <title>Tahoe-LAFS - Reliability Tool</title> <link href="/tahoe.css" rel="stylesheet" type="text/css"/> <link href="/icon.png" rel="shortcut icon" /> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> </head> <body> <h1>Tahoe-LAFS Reliability Tool</h1> <p>Given certain assumptions, this page calculates probability of share loss over time, to help make informed decisions about how much redundancy and repair bandwidth to configure on a Tahoe-LAFS grid.</p> <div n:render="forms" /> <h2>Simulation Results</h2> <p>At the end of the report span (elapsed time <span n:render="report_span" />), the simulated file had the following properties:</p> <ul> <li>Probability of loss (no maintenance): <span n:render="P_loss_unmaintained"/></li> <li>Probability of loss (with maintenance): <span n:render="P_loss_maintained"/></li> <li>Average repair frequency: once every <span n:render="P_repair_rate"/> secs</li> <li>Average shares generated per repair: <span n:render="P_repair_shares"/></li> </ul> <p>This table shows how the following properties change over time:</p> <ul> <li>P_repair: the chance that a repair was performed in the most recent check period.</li> <li>P_dead (unmaintained): the chance that the file will be unrecoverable without periodic check+repair</li> <li>P_dead (maintained): the chance that the file will be unrecoverable even with periodic check+repair</li> </ul> <div> <table n:render="sequence" n:data="simulation_table"> <tr n:pattern="header"> <td>t</td> <td>P_repair</td> <td>P_dead (unmaintained)</td> <td>P_dead (maintained)</td> </tr> <tr n:pattern="item" n:render="simulation_row"> <td><n:slot name="t"/></td> <td><n:slot name="P_repair"/></td> <td><n:slot name="P_dead_unmaintained"/></td> <td><n:slot name="P_dead_maintained"/></td> </tr> <tr n:pattern="empty"><td>no simulation data!</td></tr> </table> </div> </body> </html>