Processor : How to get cache information about intel xeon.

I'm looking for a way to have a precise architecture information about Xeon E5420. This processor have 4 cores and 2x6Mo cache, so 2 cores shares a 6Mo cache.

I'm working on machines that have 2 processors xeon, thus have 8 cores, and looking at /proc/cpuinfo just gives me indication about which core is on which processor.

Usually odd cores are on a processor and even cores are on the other but I didn't find a way to know which two cores on the same processor shares the 6Mo cache.

Any clue?

From stackoverflow claferri

• /proc/cpuinfo gives you physical id, core id, and cache size per core what more info do you need?

  claferri : That should be a comment ... What I need is in my question ... which two cores shares the same L2 Cache ...
  From mog

• By the way, I found a good library that provide a lstopo command that gives you exactly the topology of the system!

  It is called libtopology and is still in developpement, only avaliable using svn on INRIA's forge.

  If someone want it and don't find it, I will help :)

  From claferri