Re: some patches to read files faster (especially for baldur's gate and infinity engine games)

[Austin English]

On Mon, Jul 9, 2012 at 2:06 PM, Emmanuel Anne  wrote:
> Hello, I installed baldur's gate lately and noticed it was still slow in
> wine, especially if I install a few mods.
> See the description of the bug here :
> http://bugs.winehq.org/show_bug.cgi?id=17956
>
> So after reading the page about case insensitive filesystems there
> http://wiki.winehq.org/CaseInsensitiveFilenames
> I decided that one possible solution was to have everything in lower case.
> So I made a 1st patch (see attachement).
> After this, installing a weidu mod in baldur's gate becomes faster, but
> loading a savegame is still very slow compared to windows.
>
> After some more investigation using strace, it's because the program uses
> NtQueryDirectoryFile to check if a file is present in the override directory
> instead of trying to open it directly, which produces a getdents call in
> linux, which is extremely unefficient. So I just added a short cut for this
> function : if the filename argument has no wildcard, then just use stat to
> return wether the file exists or not. This is in the 2nd patch.
> After this, loading savegames was extremely fast, comparable to windows
> speed, finally, and there are no more slowdowns in game, it runs smoothly
> all the time !
>
> Well I am sure you'll find I didn't make them the right way, but I hope the
> ideas will be useful to you and that you'll merge them in one form or
> another into wine.
> Oh yes, after applying them, all the new files created by wine will be in
> lower case, but you'll eventually have to convert all the files to lower
> case in the wine directories (it's required at least in the baldur's gate 2
> directory).
> Also having a wineprefix with mixed lower and upper case characters would
> create problems.
> But except that, it works excessively well ! :)
> So maybe you'll want this enabled only if the user explecitely chooses to
> enable it.
> For me I know I'll keep it !
> I attach the simple perl script I used to convert everything to lower case.

It would be great to document this patch at
http://wiki.winehq.org/InterestingPatches.