Re: [PATCH] z3fold: use per-cpu unbuddied lists

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From	Andrew Morton <akpm@linux-foundation.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH] z3fold: use per-cpu unbuddied lists
Date	Thu, 03 Aug 2017 01:10:01 +0200
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On Wed, 2 Aug 2017 12:25:05 +0200 Vitaly Wool <vitalywool@gmail.com> wrote:

> z3fold is operating on unbuddied lists in a simple manner: in fact,
> it only takes the first entry off the list on a hot path. So if the
> z3fold pool is big enough and balanced well enough, considering
> only the lists local to the current CPU won't be an issue in any
> way, while random I/O performance will go up.

Has the performance benefit been measured?  It's a large patch.

> This patch also introduces two worker threads which: one for async
> in-page object layout optimization and one for releasing freed
> pages.

Why?  What are the runtime effects of this change?  Does this turn
currently-synchronous operations into now-async operations?  If so,
what are the implications of this if, say, the workqueue doesn't get
serviced for a while?

etc.  Sorry, but I'm not seeing anywhere near enough information and
testing results to justify merging such a large and intrusive patch.

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[PATCH] z3fold: use per-cpu unbuddied lists Vitaly Wool <vitalywool@gmail.com> - 2017-08-02 12:30 +0200
  Re: [PATCH] z3fold: use per-cpu unbuddied lists kbuild test robot <lkp@intel.com> - 2017-08-02 16:00 +0200
  Re: [PATCH] z3fold: use per-cpu unbuddied lists Andrew Morton <akpm@linux-foundation.org> - 2017-08-03 01:10 +0200

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