Re: Autoloading WAS: normal/cmdline bug & patch

[Jeroen Dekkers]

At Sat, 19 Jun 2004 18:01:45 +0200,
Marco Gerards wrote:
> 
> "Yoshinori K. Okuji" <address@hidden> writes:
> 
> > for each loaded filesystem module:
> >   try the filesystem with a specified partition/disk
> >   return if successful
> > for each non-loaded filesystem module:
> >   load the filesystem module
> >   try the filesystem
> >   return if successful
> >   unload the filesystem module
> 
> This is like what I proposed, with the difference of unloading the
> module.  I don't think the memory usage is *that* high.
> 
> For example, there are 15 filesystems that should be tried.  The
> filesystems that we have now (ext2, fat, ufs and minixfs) are all
> about 4KB.  I want to make some changes (sharing code) so that will
> become smaller, but there will be more complex filesystem.  Let's
> assume for now the average filesystem module will be 5KB.  In that
> case (15*5) 75KB will be used as max.
> 
> To me that looks like low memory usage, less than reloading those
> modules all the time.  For the apple it is no problem to use a lot of
> memory.  I don't think there are problems for the pc, unless we have
> to use <1MB.
> 
> So I think it is not needed to unload those filesystems and that
> keeping those loaded will only boost performance.  If it is required
> we can use (as Tomas proposed, IIRC) a user setable variable to
> indicate if modules should be unloaded or not.

If you try to allocate memory and there isn't anything available, it
will first invalidate all caches and after that unload all unused
modules. So I don't think it will be a big problem.

Jeroen Dekkers