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<br><div><div>On Oct 24, 2007, at 9:18 , Brian Beuning wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><div><font face="Arial" color="#0000ff" size="2"><span class="953282514-24102007">Memcached as it is today provides a certain good level of reliability</span></font></div><div><font face="Arial" color="#0000ff" size="2"><span class="953282514-24102007">(with blazing performance). <span class="Apple-converted-space"> </span></span></font><font face="Arial" color="#0000ff" size="2"><span class="953282514-24102007">Some situations are going to require more</span></font></div><div><font face="Arial" color="#0000ff" size="2"><span class="953282514-24102007">reliability, and one way<span class="Apple-converted-space"> </span></span></font><font face="Arial" color="#0000ff" size="2"><span class="953282514-24102007">to get that is replication. If there is another way</span></font></div><div><font face="Arial" color="#0000ff" size="2"><span class="953282514-24102007">to get more reliability<span class="Apple-converted-space"> </span></span></font><font face="Arial" color="#0000ff" size="2"><span class="953282514-24102007">I am very interested in hearing about it.</span></font></div></span></blockquote><div><br class="webkit-block-placeholder"></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>From Wikipedia:<br class="webkit-block-placeholder"></div><div><br class="webkit-block-placeholder"></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>In computer science, a cache is a collection of data duplicating original values stored elsewhere or computed earlier, where the original data is expensive to fetch (due to longer access time) or to compute, compared to the cost of reading the cache.</div><div><br></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>It's specifically not *supposed* to be reliable, it's just supposed to be faster than using whatever originally held your data. It's designed to throw stuff away when it notices you don't care about it at times.<br class="webkit-block-placeholder"></div><div><br class="webkit-block-placeholder"></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>It sounds like what you're looking for is a resilient dht. Maybe chord would be more appropriate for your application.<br class="webkit-block-placeholder"></div><br><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><div><font face="Arial" color="#0000ff" size="2"><span class="953282514-24102007">MySQL without ACID transactions supports a certain level of reliability.</span></font></div><div><font face="Arial" color="#0000ff" size="2"><span class="953282514-24102007">Some situations using MySQL need more reliability so MySQL added</span></font></div><div><font face="Arial" color="#0000ff" size="2"><span class="953282514-24102007">the<span class="Apple-converted-space"> </span></span></font><font face="Arial" color="#0000ff" size="2"><span class="953282514-24102007">ACID backend.</span></font></div></span></blockquote><br></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>Databases *are* supposed to be reliable. MySQL has had and continues to have data reliability problems, many by design, throughout its entire existence. Innobase Oy (not MySQL AB) created a backend that allows you to have some tables participate in transactions for common (but not all) operations.<br class="webkit-block-placeholder"></div><div><br class="webkit-block-placeholder"></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>Obviously many people feel that MySQL is good enough for their data, but your whole concept is backwards here:<br class="webkit-block-placeholder"></div><div><br class="webkit-block-placeholder"></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>1) You should be able to assume that everything you've committed to your DB will reliably come out the same way no matter what.<br class="webkit-block-placeholder"></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>2) You should assume that whatever you put into your cache may never make it back out alive and you'll have to reconstruct it from whatever the origin is.<br class="webkit-block-placeholder"></div><div><br></div><div> <span class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><div>-- </div><div>Dustin Sallings</div><br class="Apple-interchange-newline"></span> </div><br></body></html>