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Message-ID: <11814119-0e5c-3e4f-29c4-d2e9b8dfb622@suse.cz>
Date:   Tue, 22 Mar 2022 16:10:46 +0100
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Subject: Re: [PATCH 1/2] mm/page_owner.c: introduce vmalloc allocator for
 page_owner
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To:     Yinan Zhang <zhangyinan2019@email.szu.edu.cn>,
        Matthew Wilcox <willy@infradead.org>
Cc:     akpm@linux-foundation.org, william.kucharski@oracle.com,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        yejiajian2018@email.szu.edu.cn, hanshenghong2019@email.szu.edu.cn,
        caoyixuan2019@email.szu.edu.cn, zhaochongxi2019@email.szu.edu.cn,
        yuhongf@szu.edu.cn
References: <20220322032225.1402992-1-zhangyinan2019@email.szu.edu.cn>
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 <299aef9a-dd57-2197-f3cf-6b08c441f755@email.szu.edu.cn>
From:   Vlastimil Babka <vbabka@suse.cz>
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On 3/22/22 15:48, Yinan Zhang wrote:
> on 2022/3/22 11:28, Matthew Wilcox wrote:
> 
>> On Tue, Mar 22, 2022 at 11:22:24AM +0800, Yinan Zhang wrote:
>>> An application's memory consumption is high and keeps increasing,
>>> then it is suspected of having memory leak. There are several
>>> commonly used memory allocators: slab, cma, vmalloc, etc. The memory
>>> leak identification can be speed up if page information allocated
>>> by an individual allocator are analyzed individually. This patch
>>> introduce vmalloc allocator for page_owner.
>> Why is /proc/vmallocinfo not enough?
> 
> There is only one owner information in /proc/vmallocinfo: caller.
> While there are plenty of owner information in page owner,
> besides caller, it includes task id (pid), process id (tgid),
> and other useful information, which enables us for more comprehensive
> page allocation/release relevant statistics and analysis.
> 
> Adding allocator infomation can augment page owner for tracking about
> who allocates each page. And this patch adds vmalloc allocator infomation.

Hm but page_owner has the whole stack trace of allocation so it should be
easy to determine vmalloc from slab etc? How exactly would this extra field
help?