1IBV_MODIFY_QP_RATE_LIMIT(L3i)bibverbs Programmer's ManuIaBlV_MODIFY_QP_RATE_LIMIT(3)
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6 ibv_modify_qp_rate_limit - modify the send rate limits attributes of a
7 queue pair (QP)
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10 #include <infiniband/verbs.h>
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12 int ibv_modify_qp_rate_limit(struct ibv_qp *qp, struct ibv_qp_rate_limit_attr *attr);
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15 ibv_modify_qp_rate_limit() modifies the send rate limiting packet pac‐
16 ing attributes of QP qp with the attributes in attr. The argument attr
17 is an ibv_qp_rate_limit_attr struct, as defined in <infini‐
18 band/verbs.h>.
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20 The rate_limit defines the MAX send rate this QP will send as long as
21 the link in not blocked and there are work requestes in send queue.
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23 Finer control for shaping the rate limit of a QP is achieved by defin‐
24 ing the max_burst_sz, single burst max bytes size and the typi‐
25 cal_pkt_sz, typical packet bytes size. These allow the device to adjust
26 the inter-burst gap delay required to correctly shape the scheduling of
27 sends to the wire in order to reach for requested application require‐
28 ments.
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30 Setting a value of 0 for max_burst_sz or typical_pkt_sz will use the
31 devices defaults. typical_pkt_sz will default to the port's MTU value.
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33 struct ibv_qp_rate_limit_attr {
34 uint32_t rate_limit; /* kbps */
35 uint32_t max_burst_sz; /* bytes */
36 uint16_t typical_pkt_sz; /* bytes */
37 };
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40 ibv_modify_qp_rate_limit() returns 0 on success, or the value of errno
41 on failure (which indicates the failure reason).
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44 EINVAL
45 Invalid arguments.
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47 ENOSYS
48 Function is not implemented for this device.
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51 ibv_create_qp(3), ibv_destroy_qp(3), ibv_modify_qp(3), ibv_query_qp(3)
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54 Alex Rosenbaum <alexr@mellanox.com>
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56 Bodong Wang <bodong@mellanox.com>
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60libibverbs 2018-01-09 IBV_MODIFY_QP_RATE_LIMIT(3)