Subject: bug#33708: closed (Re: bug#33708: 26.1.90; nhexl-mode performance)

From: [email-masked] (GNU bug Tracking System)
Date: Fri, 14 Dec 2018 22:53:02 +0000

Your bug report

#33708: 26.1.90; nhexl-mode performance

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to [email-masked].

-- 
33708: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=33708
GNU Bug Tracking System
Contact [email-masked] with problems

Subject: Re: bug#33708: 26.1.90; nhexl-mode performance
From: Stefan Monnier <[email-masked]>
To: Guido Kraemer <[email-masked]>
Date: Fri, 14 Dec 2018 17:52:31 -0500
List-Id: <debbugs-submit.debbugs.gnu.org>

> - Thanks for fixing this, performance is great now!

Thanks for confirming.

> - Sorry for using that weird site for file sharing, you could have installed
> the bitcoin client (which is MIT licensed) and downloaded the
> blockchain ;-),

I hesitated to do that, indeed.

> what would you use for ad-hoc file sharing?

I'd put it on my web server, not linked from any page.

> - I think there is another minor bug: When the cursor is at the very
> beginning of the buffer and you search for the byte sequence at the very
> beginning of the file, search will jump to the second occurrence. Happens in
> the example of the original bug report.

Yeah, it's a misfeature that I'm not sure how to fix:

When you type `C-s f a`, you first search for `f` and this one is not
treated as a hex-search so it jumps to the first `f` char, so when you
get to type `a` Isearch keeps searching from that `f` rather than
restarting from the beginning of the buffer.

I could change the rule so that `C-s f` already treats `f` as
a hex-search, I guess.

        Stefan

Subject: 26.1.90; nhexl-mode performance
From: Guido Kraemer <[email-masked]>
To: [email-masked]
Date: Tue, 11 Dec 2018 18:06:40 +0100
List-Id: <debbugs-submit.debbugs.gnu.org>

Filing a bug report because of the discussion on

https://emacs.stackexchange.com/questions/46492/how-to-search-for-a-sequence-of-bytes-in-hexl-mode/ 

nhexl-mode performance is really bad in large files.

Occurred in the files of the Bitcoin blockchain. The beginning of every
block is marked with the byte sequence `f9beb4d9`. Searching for this
byte sequence in nhexl-mode is really slow.

In case you do not have the bitcoin client installed, I uploaded the
first file of the blockchain here (134MB, link will be valid for 30
days):

https://ufile.io/z08bl

Thanks for looking into this.

Guido.

In GNU Emacs 26.1.90 (build 1, x86_64-pc-linux-gnu, X toolkit, Xaw 
scroll bars)
of 2018-12-01 built on uranus
Repository revision: 7851ae8b443c62a41ea4f4440512aa56cc87b9b7
Windowing system distributor 'The X.Org Foundation