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Hi Dustin!<div><br><div><div>On Oct 3, 2007, at 4:17 PM, Dustin Sallings wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div><span class="Apple-style-span" style="-webkit-text-stroke-width: -1; "><span class="Apple-tab-span" style="white-space:pre"> </span>Tags seem to be getting hot and lots of people have talked about it fairly abstractly. I wanted to try to bring some of those together with respect to a memcached implementation and sit back and watch it all happen. :)</span></div><div><br class="webkit-block-placeholder"></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>Firstly, I think there are two new commands to implement tags:</div><div><br class="webkit-block-placeholder"></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>1) add_tag (key, tag_name)<br class="webkit-block-placeholder"></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>2) invalidate_tag (tag_name)<br class="webkit-block-placeholder"></div><div><br class="webkit-block-placeholder"></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>I don't think there's a need for tag inspection for a given object. There is *definitely* no command to search by tag.</div></blockquote><div><br class="webkit-block-placeholder"></div>It would be nice to do three additional things with tags:</div><div><br class="webkit-block-placeholder"></div><div>1) Get a list of all active keys associated with a tag (even if it is lossy). Two optimizations would be:</div><div> * Give me the count of objects within this tag</div><div> * For a read, take a snapshot version of the list to have read consistency (aka take an MVCC approach)</div><div><br class="webkit-block-placeholder"></div><div>2) Allow the "set" of an object with its tag name. This will solve the problem of creating an object and then tagging the object.</div><div><br class="webkit-block-placeholder"></div><div>3) Clear an object from a tag.</div><div><br class="webkit-block-placeholder"></div><div>4) Option to invalidate a tag, and blow away all keys associated with it (think of it as a mini-operation to save on round trips)</div><div><br><blockquote type="cite"><div><span class="Apple-style-span" style="-webkit-text-stroke-width: -1; "><span class="Apple-tab-span" style="white-space:pre"> </span>[It's unclear whether it's worth the effort to ever release a tag once it's been added. If we assume that tags live forever, we don't have to refcount them and a few things get easier. Any opinions?]</span></div></blockquote><div><br class="webkit-block-placeholder"></div>If you invalidate a tag, the tag should go away. </div><div><br class="webkit-block-placeholder"></div><div>Cheers,</div><div><span class="Apple-tab-span" style="white-space:pre"> </span>-Brian<br class="webkit-block-placeholder"></div><div><br class="webkit-block-placeholder"></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; "><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 style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">--</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">_______________________________________________________</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Brian "Krow" Aker, brian at tangent.org</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Seattle, Washington</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><a href="http://krow.net/"><span class="Apple-style-span" style="color: rgb(0, 0, 238); -khtml-text-decorations-in-effect: underline; "><span class="Apple-style-span" style="color: rgb(0, 0, 238); -khtml-text-decorations-in-effect: underline; ">http://krow.net</span></span></a>/ <-- Me</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><a href="http://tangent.org/"><span class="Apple-style-span" style="color: rgb(0, 0, 238); -khtml-text-decorations-in-effect: underline; "><span class="Apple-style-span" style="color: rgb(0, 0, 238); -khtml-text-decorations-in-effect: underline; ">http://tangent.org</span></span></a>/ <-- Software</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><a href="http://exploitseattle.com">http://exploitseattle.com</a>/ <-- Fun</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">_______________________________________________________</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">You can't grep a dead tree.</div><br class="Apple-interchange-newline"></span></span> </div><br></div></body></html>