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Date:   Sat, 31 Aug 2019 00:52:17 +0800
From:   Gao Xiang <gaoxiang25@huawei.com>
To:     Christoph Hellwig <hch@infradead.org>
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Subject: Re: [PATCH v8 20/24] erofs: introduce generic decompression backend
Message-ID: <20190830165217.GB107220@architecture4>
References: <20190815044155.88483-1-gaoxiang25@huawei.com>
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Hi Christoph,

On Fri, Aug 30, 2019 at 09:35:34AM -0700, Christoph Hellwig wrote:
> On Thu, Aug 15, 2019 at 12:41:51PM +0800, Gao Xiang wrote:
> > +static bool use_vmap;
> > +module_param(use_vmap, bool, 0444);
> > +MODULE_PARM_DESC(use_vmap, "Use vmap() instead of vm_map_ram() (default 0)");
> 
> And how would anyone know which to pick?

It has significant FIO benchmark difference on sequential read least on arm64...
I have no idea whether all platform vm_map_ram() behaves better than vmap(),
so I leave an option for users here...

Thanks,
Gao Xiang