From: mengkanglai <mengkanglai2@huawei.com>
To: "David S. Miller" <davem@davemloft.net>,
Eric Dumazet <edumazet@google.com>,
Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
Jiri Pirko <jiri@resnulli.us>, Simon Horman <horms@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
"Sebastian Andrzej Siewior" <bigeasy@linutronix.de>,
Lorenzo Bianconi <lorenzo@kernel.org>,
"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
open list <linux-kernel@vger.kernel.org>
Cc: "Fengtao (fengtao, Euler)" <fengtao40@huawei.com>,
"Yanan (Euler)" <yanan@huawei.com>
Subject: cpu performance drop between 4.18 and 5.10 kernel?
Date: Wed, 22 May 2024 07:44:34 +0000 [thread overview]
Message-ID: <9fd382fb581e47a291ed31bfe091112c@huawei.com> (raw)
Dear maintainers:
I updated my VM kernel from 4.18 to 5.10, and found that the CPU SI usage was higher under the 5.10 kernel for the same udp service.
I captured the flame graph and compared the two versions of kernels.
Kernel 5.10 compared to 4.18 napi_complete_done function added gro_normal_list call (ommit 323ebb61e32b4 ("net: use listified RX for handling GRO_NORMAL
skbs") Introduced), I removed gro_normal_list from napi_complete_done in 5.10 kernel, CPU SI usages was same as 4.18.
I don't know much about GRO, so I'm not sure if it can be modified in this way, and the consequences of such a modification?
next reply other threads:[~2024-05-22 7:44 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-22 7:44 mengkanglai [this message]
2024-05-22 11:08 ` cpu performance drop between 4.18 and 5.10 kernel? Edward Cree
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