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Date:   Sat, 2 Sep 2023 15:55:29 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Ze Zuo <zuoze1@huawei.com>
Cc:     <minchan@kernel.org>, <senozhatsky@chromium.org>,
        <axboe@kernel.dk>, <ying.huang@intel.com>,
        <aneesh.kumar@linux.ibm.com>, <linux-mm@kvack.org>,
        <linux-kernel@vger.kernel.org>, <linux-block@vger.kernel.org>,
        <wangkefeng.wang@huawei.com>
Subject: Re: [PATCH 1/2] zram: add a parameter "node_id" for zram
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On Fri, 1 Sep 2023 15:19:41 +0800 Ze Zuo <zuoze1@huawei.com> wrote:

> Add a parameter "node_id" to zram to support storing pages on specific
> node_id node memory.

Please document this in Documentation/admin-guide/blockdev/zram.rst

Should it be a group of nodes rather than a single one?  If this
feature is useful, people will want that.

> Now, zram memory allocation is random, however in some cases, specifying
> specific nodes for memory allocation for zram may have good effects. In
> addition, when memory tier is supported, demotion can be achieved not
> only through page migration,  it is also possible to apply for memory by
> specifying zram on low-speed device nodes, such as CXL memory devices,
> and compressing pages to these devices through memory reclamation to
> achieve similar effects to migration.

Are any performance testing results available from using this feature?