Hi, is there a way to access pool::get_next_size, pool::set_next_size from my own fast_pool_allocator without modifying the boost source (1.33.1). This my_fast_pool_allocator is a copy of fast_pool_allocator that tries to allocate the requested memory with next_size divided by 2 if malloc returns NULL. I added static member functions get_next_size/set_next_size to singleton_pool which works, but is there a way without modifying the boost source. If not, would it make sense to add these two methods in a future boost release. This is the allocate method of my_fast_pool_alloctor: template <typename T, typename UserAllocator, typename Mutex, unsigned NextSize> class my_fast_pool_allocator { ... static pointer allocate(const size_type n) { typedef boost::singleton_pool<boost::fast_pool_allocator_tag, sizeof(T), UserAllocator, Mutex, NextSize> mypool; pointer ret = NULL; for( ; !ret; ) { if (n == 1 ) { ret = static_cast<pointer>( mypool::malloc() ); } else { ret = static_cast<pointer>( mypool::ordered_malloc(n) ); } size_t nsize = mypool::get_next_size(); if( !ret ) // not enough memory available { if( nsize <= n ) // even less than we really need break; nsize >>= 1; // request half the size nsize = std::max( nsize, n ); // at least as much as we really need } mypool::set_next_size(nsize); } if (ret == 0) throw std::bad_alloc(); return ret; } ... }; Regards, Stefan