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Date: Tue, 28 Jul 2026 06:44:09 +0200
From: Christoph Hellwig <hch@lst.de>
To: changfengnan <changfengnan@bytedance.com>
Cc: linux-nvme@lists.infradead.org, Keith Busch <kbusch@kernel.org>,
	Jens Axboe <axboe@kernel.dk>, Christoph Hellwig <hch@lst.de>,
	Sagi Grimberg <sagi@grimberg.me>,
	Bart Van Assche <bvanassche@acm.org>,
	Andy Shevchenko <andriy.shevchenko@intel.com>,
	Thomas Gleixner <tglx@kernel.org>, Jun Zeng <jun1.zeng@intel.com>,
	Gang Cao <gang.cao@intel.com>, Jun I Jin <jun.i.jin@intel.com>,
	Liang A Fang <liang.a.fang@intel.com>, Yong Hu <yong.hu@intel.com>,
	linux-kernel@vger.kernel.org, Guzebing <guzebing@bytedance.com>
Subject: Re: [RFC PATCH] nvme-pci: adaptively poll completions on busy
 queues
Message-ID: <20260728044409.GA20140@lst.de>
References: <20260723120556.58670-1-changfengnan@bytedance.com> <d9210bcdf73fbe1ac8b6ec132865609a3ed68688.2c741811.b6d1.4c47.8747.ba7d54957ca3@bytedance.com>
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User-Agent: Mutt/1.5.17 (2007-11-01)

On Tue, Jul 28, 2026 at 10:24:52AM +0800, changfengnan wrote:
> The patch showed 50 confirmed throughput improvements, with a median gain of 25.2%
> and a maximum gain of 63.0%. Only five cases showed confirmed regressions;

Can you drill down into the regression and figure out why they happen
and if we can mitigate them?  It would be nice if we could find a way
to avoid major regressions and enable the adaptive mode by default.