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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Hi, Niyaz.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">One buffer can be registered with multiple HCAs. There is no problem with this. You just to call ibv_reg_mr multiple times.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Thx,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Hari.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Mvapich-discuss <mvapich-discuss-bounces@lists.osu.edu>
<b>On Behalf Of </b>Niyaz Murshed via Mvapich-discuss<br>
<b>Sent:</b> Tuesday, August 20, 2024 3:18 PM<br>
<b>To:</b> Niyaz Murshed via Mvapich-discuss <mvapich-discuss@lists.osu.edu><br>
<b>Cc:</b> nd <nd@arm.com><br>
<b>Subject:</b> [Mvapich-discuss] RDMA memory registration for AllGather<o:p></o:p></span></p>
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<p class="MsoNormal" style="mso-line-height-alt:.75pt"><span style="font-size:1.0pt;color:white">Hello all , I am trying to understand how a single memory buffer is registered to multiple rdma verbvs context in case there are data coming in from different interfaces.
As I understand, we can only register RDMA memory to a single protection<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;mso-ligatures:standardcontextual">Hello all ,
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-ligatures:standardcontextual"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-ligatures:standardcontextual">I am trying to understand how a single memory buffer is registered to multiple rdma verbvs context in case there are data coming in from different interfaces.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-ligatures:standardcontextual">As I understand, we can only register RDMA memory to a single protection domain which is linked to one interface.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-ligatures:standardcontextual"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-ligatures:standardcontextual">Assuming we receive data from 3 ranks on interface1 and 2 ranks from interface 2, how do these interfaces write to same common buffer ?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-ligatures:standardcontextual">How is the same buffer registered to 2 interfaces?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-ligatures:standardcontextual"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-ligatures:standardcontextual">Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-ligatures:standardcontextual">Niyaz<o:p></o:p></span></p>
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