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<div class="moz-cite-prefix">On 06/30/2014 09:26 PM, COCHE Sébastien
wrote:<br>
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<p class="MsoNormal"><span style="color:#1F497D" lang="EN-US">Thank
you for your response.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D" lang="EN-US">I
understand that the file exist only one time on the volume.
But it can be accessed in write, by many nodes (clients) at
the same time.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D" lang="EN-US">What’s
happen in those case ?</span></p>
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Nothing bad will happen to the filesystem. But the file may not be
meaningful if the applications writing to it don't synchronize
overlapping concurrent writes with fcntl locks.<br>
<br>
Pranith <br>
<blockquote
cite="mid:1F5F942CDD72D840988906E4FE5B9BC27E1B11@INFWPMES02.joinmyit.dom"
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<p class="MsoNormal"><span style="color:#1F497D" lang="EN-US"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D" lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D" lang="EN-US"><o:p> </o:p></span></p>
<div>
<p class="MsoNormal"><b><span
style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line">Sébastien
Coché,</span></b><span
style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line"><o:p></o:p></span></p>
<p class="MsoNormal" style="margin-top:6.0pt"><span
style="font-size:10.0pt;font-family:"Arial","sans-serif";mso-fareast-language:FR">Architecte
Infrastructure</span><span
style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line">
(DIP)<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line">SIGMA
Informatique –
</span><u><span
style="font-size:10.0pt;font-family:"Arial","sans-serif";color:blue;mso-fareast-language:FR;layout-grid-mode:line"><a
moz-do-not-send="true" href="http://www.sigma.fr/">www.sigma.fr</a><o:p></o:p></span></u></p>
<p class="MsoNormal"><span
style="font-size:10.0pt;font-family:"Arial","sans-serif";mso-fareast-language:FR">8
rue Newton – CS 84533 – 44245 LA CHAPELLE SUR ERDRE CEDEX<o:p></o:p></span></p>
<p class="MsoNormal" style="mso-line-height-alt:0pt"><span
style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line">Tél :
</span><span
style="font-size:10.0pt;font-family:"Arial","sans-serif";mso-fareast-language:FR">(+33)
2.53.48.92.57</span><span
style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line">
– Mob : 06 22 25 03 74</span><span
style="font-size:9.0pt;font-family:"Arial","sans-serif";mso-fareast-language:FR"><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span
style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext;mso-fareast-language:FR">De :</span></b><span
style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext;mso-fareast-language:FR">
Pranith Kumar Karampuri [<a class="moz-txt-link-freetext" href="mailto:pkarampu@redhat.com">mailto:pkarampu@redhat.com</a>] <br>
<b>Envoyé :</b> lundi 30 juin 2014 17:49<br>
<b>À :</b> COCHE Sébastien; <a class="moz-txt-link-abbreviated" href="mailto:gluster-users@gluster.org">gluster-users@gluster.org</a><br>
<b>Objet :</b> Re: [Gluster-users] Concurrent writes
management.<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<p class="MsoNormal">On 06/30/2014 07:49 PM, COCHE Sébastien
wrote:<o:p></o:p></p>
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<p class="MsoNormal"><span lang="EN-US">Hello</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US">I have a question
regarding concurrent write.</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US">How are manage those
writes ? Is there a risk of data corruption ?</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US">Is there a lock
mechanism, against corruption ? If yes, how it work ?</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US">I already had a look
to forum and documents but I did not found a deep dive
explanation.</span><o:p></o:p></p>
</blockquote>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Times New
Roman","serif";mso-fareast-language:FR">For
plain distribute volumes there exists only one file in the
volume with the data. All the operations on the file happen
just like they happen on normal filesystem. For
replicated/distributed replicated volumes there are internal
locks taken by replication feature to avoid any
in-consistencies.<br>
Please check <a moz-do-not-send="true"
href="https://github.com/gluster/glusterfs/blob/master/doc/features/afr-v1.md">https://github.com/gluster/glusterfs/blob/master/doc/features/afr-v1.md</a>
to know more about it.<br>
<br>
Pranith<br>
<br>
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US">Thank for your feedback</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US">Sorry for my poor
english ;-)</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal">Sebastien<o:p></o:p></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Times New
Roman","serif";mso-fareast-language:FR"><br>
<br>
<br>
<o:p></o:p></span></p>
<pre>_______________________________________________<o:p></o:p></pre>
<pre>Gluster-users mailing list<o:p></o:p></pre>
<pre><a moz-do-not-send="true" href="mailto:Gluster-users@gluster.org">Gluster-users@gluster.org</a><o:p></o:p></pre>
<pre><a moz-do-not-send="true" href="http://supercolony.gluster.org/mailman/listinfo/gluster-users">http://supercolony.gluster.org/mailman/listinfo/gluster-users</a><o:p></o:p></pre>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Times New
Roman","serif";mso-fareast-language:FR"><o:p> </o:p></span></p>
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