[asterisk-dev] slow slow menuselect (and proposal for a fix)

[Tzafrir Cohen]

On Sat, Dec 15, 2007 at 06:33:13AM -0800, Luigi Rizzo wrote:
> I experienced recently that menuselect and related processing is
> taking a long long time on certain platforms, particularly if you
> are using network-mounted filesystems, so investigated a bit the
> problem.
> 
> The reason seems to be that, if i am not mistaken, menuselect itself
> does a full pass on the entire set of sources to check dependencies.
> There is a second full pass, with awk being run on each source file
> while making up menuselect-tree.  This seems to happen every time
> I run 'make' in the top level, even without any change in the
> sources.
> 
> Remember we have over 300 files and 310k lines of C code now in the tree,
> which are not a problem on a fast modern machine with a fast local
> disk and large disk cache. Take one of these features away and
> you'll see a huge difference.
> 
> The attempt to put in the same file (the .c source) code, documentation
> and build dependencies is commendable. But in my opinion it is completely
> unreasonable that we have to process 300 files and 310k lines of code
> every time we run 'make', only to collect the 1000 or so lines
> that we care about (and find that they are unchanged).
> 
> I see two steps to remove this inefficiency:
>  
> 1. (simple): remove the dependency on menuselect.makeopts from a number
>         of targets, introducing it only as a dependency for makeopts
> 
> 2. (slightly harder): remove the MODULEINFO and MAKEOPTS sections
>         from foo.c source files, and put them somewhere else, either
>         in some foo.opts files that go along with them, and/or in a central
>         place for each directory

3. extracting the information at ./configure time rather than at 'make'
time.

(2) breaks the option to just drop a file into the build tree and get it
built.

-- 
               Tzafrir Cohen
icq#16849755              jabber:tzafrir.cohen at xorcom.com
+972-50-7952406           mailto:tzafrir.cohen at xorcom.com
http://www.xorcom.com  iax:guest at local.xorcom.com/tzafrir