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From:   Wei Wang <wvw@google.com>
Date:   Mon, 19 Mar 2018 03:15:11 +0000
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Subject: Re: [PATCH] mm: add config for readahead window
To:     Huang Ying <ying.huang@intel.com>
Cc:     gregkh@linuxfoundation.org, Todd Poynor <toddpoynor@google.com>,
        Wei Wang <wei.vince.wang@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Dan Williams <dan.j.williams@intel.com>,
        Michal Hocko <mhocko@suse.com>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Jan Kara <jack@suse.cz>,
        =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= <jglisse@redhat.com>,
        Hugh Dickins <hughd@google.com>,
        Matthew Wilcox <willy@infradead.org>,
        Ingo Molnar <mingo@kernel.org>,
        Sherry Cheung <SCheung@nvidia.com>,
        "Oliver O'Halloran" <oohall@gmail.com>,
        Andrey Ryabinin <aryabinin@virtuozzo.com>,
        Dennis Zhou <dennisz@fb.com>,
        Pavel Tatashin <pasha.tatashin@oracle.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
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On Sun, Mar 18, 2018 at 7:37 PM Huang, Ying <ying.huang@intel.com> wrote:

> Wei Wang <wvw@google.com> writes:

> > Android devices boot time benefits by bigger readahead window setting
from
> > init. This patch will make readahead window a config so early boot can
> > benefit by it as well.

> Can you change the source code of init to call ioctl(BLKRASET) early?

> Best Regards,
> Huang, Ying

Yes, I am sure we can work this out by not touching it in mainline kernel.
One reason to bring it up again is that we found some SoC vendor has always
set a different value than default (128) in their kernel tree.

Thanks,
Wei Wang