agree
> -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Sean Hefty > Sent: Friday, August 07, 2009 7:43 PM > To: 'Sivaselvam Narayanasamy'; [email protected] > Subject: RE: [ofw] "ibv_poll_cq" function in verbs.cpp > > >Is there any performance overhead in user mode cq polling ( > ibv_poll_cq > >function ) compared to doing the polling from kernel mode? > > Someone from Mellanox would need to confirm this, but I don't > believe so. > > The user space call basically goes directly to the provider > library. If you compare the user space code with the kernel > code (e.g. mthca_cq.c:mthca_poll_one versus > mlnx_uvp_cq.c:mthca_poll_one), they look identical. And I > don't think there's any difference writing the CQ entries for > a CQ that was allocated for a user space client versus a > kernel client. > > - Sean > > _______________________________________________ > ofw mailing list > [email protected] > http://lists.openfabrics.org/cgi-bin/mailman/listinfo/ofw > _______________________________________________ ofw mailing list [email protected] http://lists.openfabrics.org/cgi-bin/mailman/listinfo/ofw
