bug#33708: 26.1.90; nhexl-mode performance

[Guido Kraemer]

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