Re: [PATCH v8 0/6] optimize memblock_next_valid_pfn and early_pfn_valid on arm and arm64

[Jia He]

On 5/5/2018 12:53 AM, Pavel Tatashin Wrote:
> > 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.
Thanks for the information. I checked the config in my armv8a server,
DEFERRED_STRUCT_PAGE_INIT has not been enabled yet.And my server is
single socket.

Cheers.
Jia