Hi! In spite of compiling with NDEBUG set: g++ -Wall -D_REENTRANT -msse2 -mfpmath=sse -Wno-deprecated -DNDEBUG -c -O3 -I/home/gdupret/.local/lib64/include/ -MMD -MP -MF build/Release/GNU-Linux-x86/Model.o.d -o build/Release/GNU-Linux-x86/Model.o Model.cpp, inserting into a multi_index_container is excruciatingly slow. I have a large nbr. of elements to insert (10^5) but even the first 1000 are very slow. I also set: #ifndef NDEBUG #define NDEBUG #endif #ifdef BOOST_MULTI_INDEX_ENABLE_INVARIANT_CHECKING #undef BOOST_MULTI_INDEX_ENABLE_INVARIANT_CHECKING #endif #ifdef BOOST_MULTI_INDEX_ENABLE_SAFE_MODE #undef BOOST_MULTI_INDEX_ENABLE_SAFE_MODE #endif in the header calling the multi_index_container, but I see no change. Any suggestion on how I should do? Best ge