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   ibv_modify_qp_rate_limit    ( 3 )

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Имя (Name)

ibv_modify_qp_rate_limit - modify the send rate limits attributes
       of a queue pair (QP)

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Синопсис (Synopsis)

#include <infiniband/verbs.h>

       int ibv_modify_qp_rate_limit(struct ibv_qp *qp, struct ibv_qp_rate_limit_attr *attr);

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Описание (Description)

ibv_modify_qp_rate_limit() modifies the send rate limiting packet
       pacing attributes of QP qp with the attributes in attr.  The
       argument attr is an ibv_qp_rate_limit_attr struct, as defined in
       <infiniband/verbs.h>.

       The rate_limit defines the MAX send rate this QP will send as
       long as the link in not blocked and there are work requests in
       send queue.

       Finer control for shaping the rate limit of a QP is achieved by
       defining the max_burst_sz, single burst max bytes size and the
       typical_pkt_sz, typical packet bytes size. These allow the device
       to adjust the inter-burst gap delay required to correctly shape
       the scheduling of sends to the wire in order to reach for
       requested application requirements.

       Setting a value of 0 for max_burst_sz or typical_pkt_sz will use
       the devices defaults.  typical_pkt_sz will default to the port's
       MTU value.

       struct ibv_qp_rate_limit_attr {
               uint32_t        rate_limit;     /* kbps */
               uint32_t        max_burst_sz;   /* bytes */
               uint16_t        typical_pkt_sz; /* bytes */
       };

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Возвращаемое значение (Return value)

ibv_modify_qp_rate_limit() returns 0 on success, or the value of
       errno on failure (which indicates the failure reason).

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Ошибки (Error)

EINVAL
       Invalid arguments.

   EOPNOTSUPP
       Function is not implemented for this device.  (ENOSYS may
       sometimes be returned by old versions of libibverbs).

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Смотри также (See also)

ibv_create_qp(3), ibv_destroy_qp(3), ibv_modify_qp(3),
       ibv_query_qp(3)

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