ruby: recorder: Fix (de-)serializing with different cache block-sizes

Upon aggregating records, serialize system's cache-block size, as the
cache-block size can be different when restoring from a checkpoint. This way,
we can correctly read all records when restoring from a checkpoints, even if
the cache-block size is different.

Note, that it is only possible to restore from a checkpoint if the
desired cache-block size is smaller or equal to the cache-block size
when the checkpoint was taken; we can split one larger request into
multiple small ones, but it is not reliable to do the opposite.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>

src/sim/serialize.hh

@@ -58,7 +58,7 @@ class EventQueue;
  * SimObject shouldn't cause the version number to increase, only changes to
  * existing objects such as serializing/unserializing more state, changing sizes
  * of serialized arrays, etc. */
-static const uint64_t gem5CheckpointVersion = 0x0000000000000009;
+static const uint64_t gem5CheckpointVersion = 0x000000000000000a;
 
 template <class T>
 void paramOut(std::ostream &os, const std::string &name, const T &param);