Now repository indexes (o.n.m.c.repository.sfs.SimpleFileIndex) reside in memory (they are based on ConcurrentHashMap).
Measurement made on ~1200-files project shows that these indexes consume about 10% of the overall memory.
These indexes should be able to swap to disk.
This bug was reported against NetBeans IDE 6.0 or an older release, or against a non-maintained module. NetBeans team does not have enough resources to get to this issue, therefore we are closing the issue as a WONTFIX. If you are interested in providing a patch for this bug, please see our NetFIX guidelines for how to proceed.
We apologize for any inconvenience.
The NetBeans Team