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Date: Thu, 30 May 2024 08:16:53 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Yunsheng Lin <linyunsheng@huawei.com>
Cc: <davem@davemloft.net>, <pabeni@redhat.com>, <netdev@vger.kernel.org>,
 <linux-kernel@vger.kernel.org>, Alexander Duyck
 <alexander.duyck@gmail.com>, Andrew Morton <akpm@linux-foundation.org>,
 <linux-mm@kvack.org>
Subject: Re: [PATCH net-next v5 01/13] mm: page_frag: add a test module for
 page_frag
Message-ID: <20240530081653.769e4377@kernel.org>
In-Reply-To: <1cba403b-a2c7-5706-78b7-91ccc6caa53b@huawei.com>
References: <20240528125604.63048-1-linyunsheng@huawei.com>
	<20240528125604.63048-2-linyunsheng@huawei.com>
	<20240529172938.3a83784d@kernel.org>
	<1cba403b-a2c7-5706-78b7-91ccc6caa53b@huawei.com>
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On Thu, 30 May 2024 17:17:17 +0800 Yunsheng Lin wrote:
> > Is this test actually meaningfully testing page_frag or rather
> > the objpool construct and the scheduler? :S  
> 
> For the objpool part, I guess it is ok to say that it is a
> meaningfully testing for both page_frag and objpool if there is
> changing to either of them.

Why guess when you can measure it. 
Slow one down and see if it impacts the benchmark.

> For the scheduler part, this test provides the below module param
> to avoid the the noise from scheduler.
> 
> +static int test_push_cpu;
> +module_param(test_push_cpu, int, 0600);
> +MODULE_PARM_DESC(test_push_cpu, "test cpu for pushing fragment");
> +
> +static int test_pop_cpu;
> +module_param(test_pop_cpu, int, 0600);
> +MODULE_PARM_DESC(test_pop_cpu, "test cpu for popping fragment");
> 
> Or is there any better idea for testing page_frag?