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From: William Tu <u9012063@gmail.com>
To: Xdp <xdp-newbies@vger.kernel.org>
Cc: "Karlsson, Magnus" <magnus.karlsson@intel.com>,
	"Björn Töpel" <bjorn.topel@intel.com>
Subject: xdpsock poll syscall CPU 100%
Date: Thu, 20 Feb 2020 14:49:17 -0800	[thread overview]
Message-ID: <CALDO+SZmCxtWCeqh93HO6vm1KHh_UGxMby+td2ba_o66ZT+MVQ@mail.gmail.com> (raw)

Hi,

I'm trying to save some CPU cycles when there is no packet arrives.
I enable the poll syscall option of xdpsock, by doing

$ ./xdpsock -r -p -S -i ens16
 sock0@ens160:0 rxdrop xdp-skb poll()
                pps         pkts        1.00
rx              0           0
tx              0           0

Since there is no packet coming, I though by calling poll()
system call, the xdpsock process will be blocked and CPU utilization
should be way under 100%. However, I'm still seeing 100%
CPU utilization. Am I understanding this correctly?

Thanks,
William

             reply	other threads:[~2020-02-20 22:49 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-20 22:49 William Tu [this message]
2020-02-21  8:11 ` xdpsock poll syscall CPU 100% Magnus Karlsson
2020-02-21  8:28 ` Eelco Chaudron
2020-02-21  8:33   ` Magnus Karlsson
2020-02-21  8:40     ` Eelco Chaudron
2020-02-21  8:46       ` Magnus Karlsson
2020-02-21  9:23         ` Eelco Chaudron
2020-02-21 18:40         ` William Tu

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