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From: "Walukiewicz, Miroslaw" <Miroslaw.Walukiewicz@intel.com>
To: "dev@dpdk.org" <dev@dpdk.org>
Thread-Topic: determine number of free TX descriptors in DPDK transmit queue
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Date: Mon, 30 Mar 2015 09:51:13 +0000
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Subject: [dpdk-dev] determine number of free TX descriptors in DPDK transmit
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Hello,

Is there any method of determining the number free TX descriptor in specifi=
c TX queue?

I know that when transmit function is called with some number packets to se=
nd and then number returned by function is different than provided that mea=
ns that queue is full.

This mechanism works good when we have packets that fits single DPDK descri=
ptor (rte_mbuf).

But when we provide longer descriptors for example up to 64K-long packets w=
ith different size it is good to predict how much space is available in the=
 transmit queue, because creating such longs packets Is expensive and the a=
pplication could work much more effectively when such information would be =
provided.

Regards,

Mirek