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From: "Morten Brørup" <mb@smartsharesystems.com>
To: <bruce.richardson@intel.com>
Cc: "Ian Stokes" <ian.stokes@intel.com>, <dev@dpdk.org>
Subject: rte_eth_stats_get seems slow
Date: Fri, 25 Apr 2025 13:52:55 +0200	[thread overview]
Message-ID: <98CBD80474FA8B44BF855DF32C47DC35E9FC02@smartserver.smartshare.dk> (raw)

Bruce,

rte_eth_stats_get() on Intel NICs seems slow to me.

E.g. getting the stats on a single port takes ~132 us (~451,000 CPU cycles) using the igb driver, and ~50 us using the i40e driver.

Referring to the igb driver source code [1], it's 44 calls to E1000_READ_REG(), so the math says that each one takes 3 us (~10,000 CPU cycles).

Is this expected behavior?

It adds up, e.g. it takes a full millisecond to fetch the stats from eight ports using the igb driver.

[1]: https://elixir.bootlin.com/dpdk/v24.11.1/source/drivers/net/e1000/igb_ethdev.c#L1724


Med venlig hilsen / Kind regards,
-Morten Brørup


                 reply	other threads:[~2025-04-25 11:53 UTC|newest]

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