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    SubjectRe: [PATCH 01/10] IB/ehca: Support for multiple event queues
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    Roland Dreier <rdreier@cisco.com> wrote on 16.07.2007 18:04:26:
    > Do you have any data on how well this round-robin assignment works?
    > It seems not quite right to me for the driver to advertise nr_eqs
    > completion vectors, but then if round-robin is turned on to ignore the
    > consumer's decision about which vector to use.
    No, I've no figures to provide here. The background of this dist_eqs
    option is actually to allow us testing across all event queues
    without to change the testcases resp consumers to use certain
    event queue number. Thus, I should comment it as EXPERIMENTAL?
    > Maybe if round-robin is turned on you should report 0 as the number of
    > completion vectors? Or maybe we should allow well-known values for
    > the completion vector passed to ib_create_cq to allow consumers to
    > specify a policy (like round robin) instead of a particular vector?
    > Maybe the whole interface is broken and we should only be exposing
    > policies to consumers instead of the specific vector?
    Agree in that device driver should not overwrite consumer's policy
    of event queue assigment. Since dist_eqs is disabled as default,
    there's no issue, isn't it?
    Regarding ib_verbs: perhaps we should provide create/destroy_eq()
    and let upper level protocols or consumers dictate the assignment
    to cq by passing an event queue pointer to create_cq()...
    > I think I would rather hold off on multiple EQs for this merge window
    > and plan on having something really solid and thought-out for 2.6.24.
    Fair enough. However why don't let us gather experience with this
    feature now? Should we remove dist_eqs option for more consistency?
    Thanks
    Nam

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