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Subject: Re: [PATCH v8 0/6] optimize memblock_next_valid_pfn and
 early_pfn_valid on arm and arm64
To: Daniel Vacek <neelx@redhat.com>, Jia He <hejianet@gmail.com>
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From: Pavel Tatashin <pasha.tatashin@oracle.com>
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Date: Fri, 4 May 2018 12:53:40 -0400
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> I'm wondering, ain't simple enabling of config
> DEFERRED_STRUCT_PAGE_INIT provide even better speed-up? If that is the
> case then it seems like this series is not needed at all, right?
> I am not sure why is this config optional. It looks like it could be
> enabled by default or even unconditionally considering that with
> commit c9e97a1997fb ("mm: initialize pages on demand during boot") the
> deferred code is statically disabled after all the pages are
> initialized.

Hi Daniel,

Currently, deferred struct pages are initialized in parallel only on NUMA machines. I would like to make a change to use all the available CPUs even on a single socket systems, but that is not there yet. So, I believe Jia's performance improvements are still relevant.

Thank you,
Pavel