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Fragmentation of application space

Rank

Total Posts: 3

Joined 2013-01-30

PM

Hi,
In the context of managing the loading and deleting of applications on a Multos 4.2 card, I am considering the scenario in which 10 small apps are currently loaded. Say we decide to remove 5 of them, and load a bigger application which size is equivalent to the 5 removed. The question is:
could an OPEN MEL APPLICATION APDU return a ‘Insufficient memory to load application’ SW because of insufficient contiguous memory space for one of the application spaces (code, static)?

Thanks for helping.
Cheers.

     
RankRankRank

Total Posts: 74

Joined 2012-02-21

PM

Hi thanks for the question.

Memory defragmentation is technically optional in the MULTOS specifications.

However I know for sure that Multos International implementations do memory defragmentation as part of application deletion and think that Samsung implementations do the same. I’m not sure about the other implementers but could find out. Who is the implementer of the chips you are using?

You can find out by sending the GET MULTOS DATA APDU - the implementer ID is the 4th byte. The latest MUtil can send this command for you and interpret the result.

Thanks.

     
Rank

Total Posts: 3

Joined 2013-01-30

PM

Thanks Chris.
The implementer ID is 0x02 (I think it’s KeyCorp).
It would be nice indeed to have this defragmentation on delete feature.
Cheers.

     
RankRankRank

Total Posts: 74

Joined 2012-02-21

PM

KeyCorp became Multos International (same implementer id) so your chips will do the memory defragmentation.

     
Rank

Total Posts: 3

Joined 2013-01-30

PM

Thanks, that’s excellent news. One thing we won’t have to worry about.