bug#19393: 25.0.50; Emacs cannot determine coding system of ISO-8859 encoded files

[Wolfgang Jenkner]

On Tue, Jan 13 2015, Eli Zaretskii wrote:

>> From: Wolfgang Jenkner <wjenkner@inode.at>
>> Cc: 19393@debbugs.gnu.org
>> Date: Tue, 13 Jan 2015 15:06:01 +0100
>> 
>> However, if the file in question is compressed
>> revert-buffer-with-coding-system still takes 4 minutes (the user time
>> being dominated to 98% by memmove).
>
> Is the problem with compressed files due to the fact that the size is
> unknown in advance?

I only know that loading the compressed file from disk with the same
coding system conversion as above takes just a few seconds, i.e., doing
something like

C-x RET c l a t i n - 1 <return> C-x C-f m o v i e s . l i s t . g z 

is fast (enough).

> If so, perhaps enlarging by more than was
> requested (e.g., twice as large) will alleviate the problem?

IIUC, this is your previous suggestion about improving
insert-file-contents itself?