Hi, &nbsp; I had run a many-core (256) garnet standalone test using gem5-version23. And I encountered a fatal problem as shown below &nbsp;Then I entered the Set.hh, found this information. But I don't know the influence if I increase the 'bits' 's value in build_opts file. But I run the many-core simulation well in gem5-v21. It seems because gem5-v21 doesn't have the build_opts file. I wan to know that can I change this value as will in the gem5-v23? Best Wishes, Zifeng &nbsp; private: &nbsp; &nbsp; // Number of bits in use in this set. &nbsp; &nbsp; // can be defined in build_opts file (default=64). &nbsp; &nbsp; int m_nSize; &nbsp; &nbsp; std::bitset<NUMBER_BITS_PER_SET&gt; bits;