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<div class="document" id="tahoe-lafs-weekly-news-issue-number-2">
<h1 class="title">Tahoe-LAFS Weekly News, issue number 2</h1>
<p>Welcome to the Tahoe-LAFS Weekly News (TWN) brought to you by Patrick
McDonald, scribe. <a class="reference external" href="http://tahoe-lafs.org">Tahoe-LAFS</a> is a secure, distributed storage system.</p>
<div class="section" id="announcements-and-news">
<h1>Announcements and News</h1>
<p>The 1.9.0 planning has begun. The development team is evicting tickets.
Brian Warner will be posting to the tahoe-dev list regarding the 1.9.0
schedule.</p>
<p>Tuesday at the Tahoe Summit will be deep design day with Brian Warner.
While no specifics yet, deep design day will most likely cover
accounting and <a class="reference external" href="http://tahoe-lafs.org/trac/tahoe-lafs/ticket/466">signed Introducer announcements</a>. Both of these
features Brian has been working on for a long time. He is looking for
some assistance so he can land some code. Also up for discussion will
be new capability formats as MDMF caps are due in the 1.9.0 release.</p>
<p>David Triendl announced he is stepping down from his longstanding role
as manager for the public demo test grid. TWN would like to extend our
thanks to David for his supports. We greatly appreciate it. Charles
Wyble volunteered to take over the role. Charles welcome aboard, we
look forward to working with you.</p>
<p>The tahoe-dev mailing list provided an interesting discussion regarding
the access control policies Tahoe-LAFS offers. Two newcomers asked the
list about these policies to which various "old timers" provided
explanations. See <a class="reference external" href="http://tahoe-lafs.org/pipermail/tahoe-dev/2011-June/date.html">the mailing list archives</a> for the discussion and
<a class="reference external" href="http://tahoe-lafs.org/trac/tahoe-lafs/browser/trunk/docs/about.rst#access-control">the overview of Tahoe-LAFS</a> for a summary of access control features.</p>
<p>Tahoe is now a <a class="reference external" href="http://git-annex.branchable.com/forum/tips:_special__95__remotes__47__hook_with_tahoe-lafs/">special remote</a> for <a class="reference external" href="http://git-annex.branchable.com">git-annex</a>.</p>
<p><a class="reference external" href="http://forum.bitcoin.org/?topic=2236.0">210 Bitcoins</a> have been pledged to integrate Tahoe-LAFS and Bitcoin.
A new ticket, <a class="reference external" href="http://tahoe-lafs.org/trac/tahoe-lafs/ticket/1408">1408</a> was created in response to this bounty.</p>
</div>
<div class="section" id="interview-with-the-developers">
<h1>Interview with the Developers</h1>
<p>This past week, TWN interviewed Kevan. Kevan is a member of the
Tahoe-LAFS development team. Kevan is working on MDMF which is the
major feature of the upcoming 1.9.0 release. Thank Kevan for taking the
time for this interview.</p>
<p>Patrick: First give us a little introduction. Tell us a bit about who
you are?</p>
<p>Kevan: My Name is Kevan. I am 24. I live near Los Angeles. I work as
a system administrator and am slowly completing a Master's degree in
computer science.</p>
<p>Patrick: What made you decide to develop for Tahoe-LAFS?</p>
<p>Kevan: I learned about the project on a mailing list I follow; I think
it was an email Zooko sent about Tahoe-LAFS being a (last minute) entry
into the Google Summer of Code program. I looked at it, noted that it
dealt with areas which interested me and noted it was primarily written
in Python, which I was learning at the time.</p>
<p>Patrick: What areas in particular interested you?</p>
<p>Kevan: The P2P aspects, at that time. I've since grown to appreciate
the use of capabilities (and capability research in general), though I'm
not as familiar with that as I'd like to be.</p>
<p>Patrick: With the upcoming new release, the big new feature is MDMF, a
feature you are working on. Can you tell us what is MDMF?</p>
<p>Kevan: In short, MDMF is more efficient mutable files. Immutable file
have (always?) been segmented; in other words, they're processed not as
one big piece, but in little parts.</p>
<p>Current mutable files aren't segmented; they are processed in one big
chunk. There are a few significant downsides to not chunking mutable
files.</p>
<p>Patrick: Such as?</p>
<p>Kevan: Memory footprint, for one. If you want to add something to the
end of an SDMF mutable file, you have to download and decrypt the whole
thing, add your something to the end of the plaintext, then reencrypt
and reupload the result.</p>
<p>Patrick: How would the same thing work with MDMF, what would be the
difference?</p>
<p>Kevan: You'd only need to download at most the last segment (which is
probably only 128KB or so in size), and all of your operations are
performed on that. So that's less data sitting in RAM while you upload
and less data that you need to download and upload as a result of your
modification.</p>
<p>Patrick: Sounds like this would be a significant improvement in speed.</p>
<p>Kevan: Hopefully. I'm curious to see if any interesting use cases are
enabled by efficiently modified mutable files.</p>
<p>Patrick: Will you be attending the Tahoe Summit in San Franscisco?</p>
<p>Kevan: Yes, I plan to.</p>
<p>Patrick: Anything you are looking forward to at the Summit?</p>
<p>Kevan: I don't think I've ever met any of the other developers in
person, so I'm looking forward to that. I hope that we'll get close to
having MDMF ready for trunk; being in one place should help speed code
review along.</p>
<p>Patrick: Any words of wisdom for new developers looking to join the
Tahoe-LAFS dev team?</p>
<p>Kevan: Join the mailing list and introduce yourself. It's likely that
someone will point you to an easy starter ticket. In my experience, the
hardest part of getting into a new codebase is finding a place to start,
so I found that really helpful. I'm impressed with the other developers
and I know I've learned a lot by working on Tahoe-LAFS.</p>
</div>
<div class="section" id="patch-needing-review-of-the-week">
<h1>Patch Needing Review of the Week</h1>
<p>Ticket <a class="reference external" href="http://tahoe-lafs.org/trac/tahoe-lafs/ticket/1342">1342</a> needs review. This ticket, "rename tests of packaging and
improve them to avoid spurious system-dependent test failures", is to
manage small clean-up patches which we would like to see applied to
1.9.0. Review of this patch would be greatly appreciated. This <a class="reference external" href="http://tahoe-lafs.org/trac/tahoe-lafs/wiki/PatchReviewProcess">page</a>
covers the procedures for code review.</p>
</div>
<div class="section" id="bug-of-the-week">
<h1>Bug of the week</h1>
<p>Ticket <a class="reference external" href="http://tahoe-lafs.org/trac/tahoe-lafs/ticket/1395">1395</a> wins the award for bug of the week. This ticket covers an
error which occurs when doing a check --verify on files which are bigger
than 1GB. We would like to see this bug resolved in time for inclusion
in 1.9.0. We would appreciate any help the community can provide with
this ticket.</p>
</div>
<div class="section" id="company-of-the-week">
<h1>Company of the Week</h1>
<p>Starting next week, TWN will be running a company of the week section.
In this section, TWN will highlight companies which contribute to
Tahoe-LAFS. It is our way of saying thank you.</p>
</div>
<div class="section" id="related-similar-competive-project-of-the-week">
<h1>Related/Similar/Competive Project of the Week</h1>
<p>Starting next week, TWN will be running a related/similar/competitive
project of the week. In this section, we will discuss things we feel
are good with similar or even competitive projects. Please note, no
non-Free/Open projects will be covered.</p>
</div>
</div>
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