From: Stephen Hemminger <stephen@networkplumber.org>
To: Laurent Hardy <laurent.hardy@6wind.com>
Cc: dev@dpdk.org, xiaolong.ye@intel.com, qi.z.zhang@intel.com,
olivier.matz@6wind.com, david.marchand@redhat.com
Subject: Re: [dpdk-dev] [PATCH] i40evf: use non spinning delay when issuing AQ request to PF
Date: Sat, 4 Apr 2020 14:51:18 -0700 [thread overview]
Message-ID: <20200404145118.218288d9@hermes.lan> (raw)
In-Reply-To: <20200330143330.7427-1-laurent.hardy@6wind.com>
On Mon, 30 Mar 2020 16:33:30 +0200
Laurent Hardy <laurent.hardy@6wind.com> wrote:
> When a port is handled by the i40evf dpdk pmd we could observe a cpu usage
> around 70% in case of rte eth stats functions (rte_eth_stats_get and
> rte_eth_xstats_get) called periodically via an application control thread.
>
> This is due to the polling mechanism to handle communication between VF
> and PF introduced for x710 (eg: VSI and virtual channel).
>
> After issuing any request to the PF, the VF will wait in a blocking mode
> until it gets a response from the PF or until timeout (2sec).
> Instead, uses rte_delay_us_sleep to sleep for ASQ_DELAY_MS, which will
> use system sleep and will not block the CPU core.
>
> Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
> Signed-off-by: Laurent Hardy <laurent.hardy@6wind.com>
Any thing sleeping for that long (1ms) should never spin.
Is there anyway to use something like a file descriptor/interrupt
for something this long?
prev parent reply other threads:[~2020-04-04 21:51 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-30 14:33 Laurent Hardy
2020-04-04 1:51 ` Zhang, Qi Z
2020-04-04 21:51 ` Stephen Hemminger [this message]
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