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-webkit-text-stroke-width: 0px; background-color: rgb(255, 255,
255); font-family: arial;">(Resending as the prev had a wrong
Subject and was not continuing the discussion thread - hopefully
this will do better :)<br>
<br>
This discussion of geo-distributed Swift is of great interest to
us as well. Yet, based on our analysis, the proposed ring of ring
seem to not meet a basic requirement that we see. </div>
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<div style="color: rgb(34, 34, 34); font-size: small; font-style:
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-webkit-text-stroke-width: 0px; background-color: rgb(255, 255,
255); font-family: arial;">One of the basic disadvantages
(and advantages) of the consistent hashing at the core of the
Swift Ring concept is that it takes control over the placement of
objects. As long as one considers a fairly unified cluster - and
does not care which object is placed where in that cluster,
consistent hashing does a great job.</div>
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<div style="color: rgb(34, 34, 34); font-size: small; font-style:
normal; font-variant: normal; font-weight: normal; letter-spacing:
normal; line-height: normal; orphans: auto; text-align: start;
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widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto;
-webkit-text-stroke-width: 0px; background-color: rgb(255, 255,
255); font-family: arial;">However, in the case of geo-distributed
Swift, many customers do care and need control over the placement
decision - hence making the use of consistent hashing to decide
where an object should be placed will not do. We actually believe
that placement decisions can be made in the resolution of
containers - not individual objects. Hence, container sync seems
like a reasonable starting point.</div>
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normal; line-height: normal; orphans: auto; text-align: start;
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<div style="color: rgb(34, 34, 34); font-size: small; font-style:
normal; font-variant: normal; font-weight: normal; letter-spacing:
normal; line-height: normal; orphans: auto; text-align: start;
text-indent: 0px; text-transform: none; white-space: normal;
widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto;
-webkit-text-stroke-width: 0px; background-color: rgb(255, 255,
255); font-family: arial;">We plan to contribute improvements to
container sync, making it a more attractive, scalable, and easier
to use replication mechanism such that it can serve as a basis of
a placement aware system controlling where replicas reside in a
geo-distributed Swift. It would be great if the the community
align on the need to offer control over placement, between geo
distributed sites, but if this is not the case, we need to find a
way to accommodate the different requirements
without complicating the<span class="Apple-converted-space"> </span><span
class="il" style="background-color: rgb(255, 255, 204); color:
rgb(34, 34, 34); background-position: initial initial;
background-repeat: initial initial;">design</span>. </div>
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<div style="color: rgb(34, 34, 34); font-size: small; font-style:
normal; font-variant: normal; font-weight: normal; letter-spacing:
normal; line-height: normal; orphans: auto; text-align: start;
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widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto;
-webkit-text-stroke-width: 0px; background-color: rgb(255, 255,
255); font-family: arial;">Regards,</div>
<div style="color: rgb(34, 34, 34); font-size: small; font-style:
normal; font-variant: normal; font-weight: normal; letter-spacing:
normal; line-height: normal; orphans: auto; text-align: start;
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widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto;
-webkit-text-stroke-width: 0px; background-color: rgb(255, 255,
255); font-family: arial;">David Hadas<span
class="Apple-converted-space"> <br>
</span></div>
<pre class="moz-signature" cols="72">--
DH
Regards,
David Hadas
IBM Research Labs, Haifa</pre>
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