public inbox for
 help / color / mirror / Atom feed
From: Jonathan Wakely <>
To: "François Dumont" <>
Cc: "" <>,
	gcc-patches <>
Subject: Re: [PATCH] Enhance _Hashtable for range insertion 0/5
Date: Tue, 21 Jun 2022 18:12:21 +0100	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>

On Mon, 20 Jun 2022 at 17:58, François Dumont via Libstdc++
<> wrote:
> Hi
> Here is a series of patch to enhance _Hashtable behavior mostly in the
> context of range insertion. I also start considering the problem of
> memory fragmentation in this container with 2 objectives:
> - It is easier to find out when you're done with the elements of a
> bucket if the last node of the bucket N is the before-begin node of
> bucket N + 1.
> - It is faster to loop through nodes of a bucket if those node are close
> in memory, ultimately we should have addressof(Node + 1) ==
> addressof(Node) + 1

Have these changes been profiled or benchmarked? Is it measurably
faster? By how much?

> [1/5] Make more use of user hints as both insertion and allocation hints.
> [2/5] Introduce a new method to check if we are still looping through
> the same bucket's nodes
> [3/5] Consider that all initializer_list elements are going to be inserted
> [4/5] Introduce a before-begin cache policy to remember which bucket is
> currently pointing on it
> [5/5] Prealloc nodes on _Hashtable copy and introduce a new assignment
> method which replicate buckets data structure
> François

  reply	other threads:[~2022-06-21 17:12 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-06-20 16:57 François Dumont
2022-06-21 17:12 ` Jonathan Wakely [this message]
2022-06-26 20:06   ` François Dumont
2022-06-27 16:18     ` Jonathan Wakely

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:

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

  git send-email \
    --in-reply-to='' \ \ \ \ \

* 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 read-only IMAP folder(s) and NNTP newsgroup(s).