On 09/02/10 23:04, Brian Gerkey wrote:
> On Thu, Sep 2, 2010 at 8:39 AM, Cedric Pradalier
> <cedric.pradalier@mavt.ethz.ch>  wrote:
>    
>> That actually raises a question: what is the recommended procedure on a
>> read-only system. Is it better to put the cache on a tmpfs mount or is
>> it possible to generate the cache once and for all, and use it afterward?
>>      
> Either one should work, though I haven't tried them.  To avoid the
> chance of having stale data in the cache, I would go for the tmpfs
> solution (I know that it's a read-only filesystem, but bad cached
> values are a pain to debug).
>
> Note that for the one-time cache to work, you need to set
> ROS_CACHE_TIMEOUT=-1.0 in the environment.  Otherwise, rospack will
> keep trying to rebuild the cache (and won't use the cached values).
>
> 	brian.
> ____

Can I understand that I can run the following procedure:
set my system rw,
set my cache_timeout to something small,
run rostopic list (for instance),
set the system ro
set cache_timeout to -1
any subsequent call to ros, will then be able to use the cached data?

Thanks

-- 

Dr. Cedric Pradalier
http://www.asl.ethz.ch/people/cedricp