linux-bcachefs.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Kuan-Wei Chiu <visitorckw@gmail.com>
To: Kent Overstreet <kent.overstreet@linux.dev>
Cc: colyli@suse.de, bfoster@redhat.com, jserv@ccns.ncku.edu.tw,
	linux-bcache@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-bcachefs@vger.kernel.org
Subject: Re: [PATCH 0/5] Optimize number of comparisons for heap/heapsort implementaion
Date: Mon, 22 Jan 2024 00:55:51 +0800	[thread overview]
Message-ID: <Za1Ml/ZUBXdYXOIt@visitorckw-System-Product-Name> (raw)
In-Reply-To: <nl6kvjxg4gia5pbfb4jibxusvavmlwumrvy3swfs33ciub32wt@2kmeqnqycxxh>

On Sun, Jan 21, 2024 at 11:21:06AM -0500, Kent Overstreet wrote:
> On Sun, Jan 21, 2024 at 11:36:44PM +0800, Kuan-Wei Chiu wrote:
> > Hello,
> > 
> > The existing implementations of heap/heapsort follow the conventional
> > textbook approach, where each heapify operation requires approximately
> > 2*log2(n) comparisons. In this series, I introduce a bottom-up variant
> > that reduces the number of comparisons during heapify operations to
> > approximately log2(n), while maintaining the same number of swap
> > operations.
> > 
> > Thanks,
> > Kuan-Wei
> > 
> > Kuan-Wei Chiu (5):
> >   bcachefs: Optimize eytzinger0_sort() using bottom-up heapsort
> >   bcachefs: Introduce parent function for sort_cmp_size()
> >   bcachefs: Optimize sort_cmp_size() using bottom-up heapsort
> >   bcachefs: Optimize number of comparisons in heap_sift_down
> >   bcache: Optimize number of comparisons in heap_sift
> > 
> >  drivers/md/bcache/util.h |  23 +++++----
> >  fs/bcachefs/util.c       | 109 ++++++++++++++++++++++++++-------------
> >  fs/bcachefs/util.h       |  23 +++++----
> >  3 files changed, 98 insertions(+), 57 deletions(-)
> 
> Good stuff
> 
> While we're looking at this code, we should be doing some cleanup too -
> there's no reason for the heap code to be duplicated in bcache and
> bcachefs anymore, and it'd also be nice to get fs/bcachefs/eytzinger.h
> moved to include/linux and bcache converted to use it.
> 
> I also would not be surprised if there's another heap implementation in
> include/linux; we'll want to check for that and if there is decide which
> is worth keeping.
>
Yes, we have 'min_heap.h' in include/linux.

> Would you or Coli be interested in taking that on as well?

  reply	other threads:[~2024-01-21 16:55 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-01-21 15:36 [PATCH 0/5] Optimize number of comparisons for heap/heapsort implementaion Kuan-Wei Chiu
2024-01-21 15:36 ` [PATCH 1/5] bcachefs: Optimize eytzinger0_sort() using bottom-up heapsort Kuan-Wei Chiu
2024-01-21 15:36 ` [PATCH 2/5] bcachefs: Introduce parent function for sort_cmp_size() Kuan-Wei Chiu
2024-01-21 16:17   ` Kent Overstreet
2024-01-21 17:05     ` Kuan-Wei Chiu
2024-01-21 17:37       ` Kent Overstreet
2024-01-21 15:36 ` [PATCH 3/5] bcachefs: Optimize sort_cmp_size() using bottom-up heapsort Kuan-Wei Chiu
2024-01-21 15:36 ` [PATCH 4/5] bcachefs: Optimize number of comparisons in heap_sift_down Kuan-Wei Chiu
2024-01-21 15:36 ` [PATCH 5/5] bcache: Optimize number of comparisons in heap_sift Kuan-Wei Chiu
2024-01-21 16:21 ` [PATCH 0/5] Optimize number of comparisons for heap/heapsort implementaion Kent Overstreet
2024-01-21 16:55   ` Kuan-Wei Chiu [this message]
2024-01-21 17:41     ` Kent Overstreet
2024-01-22 15:06       ` Kuan-Wei Chiu
2024-01-22 16:06         ` Kent Overstreet
2024-01-22 16:23           ` Kuan-Wei Chiu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=Za1Ml/ZUBXdYXOIt@visitorckw-System-Product-Name \
    --to=visitorckw@gmail.com \
    --cc=bfoster@redhat.com \
    --cc=colyli@suse.de \
    --cc=jserv@ccns.ncku.edu.tw \
    --cc=kent.overstreet@linux.dev \
    --cc=linux-bcache@vger.kernel.org \
    --cc=linux-bcachefs@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).