> But is that system easy to understand? Yes, if you documented it properly. > Is the code easy I haven't used go, but it's easy in C. Setting up macros for

> But is that system easy to understand? Yes, if you documented it properly. > Is the code easy I haven't used go, but it's easy in C. Setting up macros for all the bit manipulation is a very common technique. Usage would be trivial - just call a couple accessor macros. It's certainly easier than walking the parse tree of a JSON record. Using a simple bitmap would also skip the initial parsing step. It's easier to use the bitmap. The "example usage" section below is very simple. Setting up ElasticSearch or fiddling with a JSON parser is more work (and a lot harder on CPU/RAM). /* the "2nd array" */ uint64 *port_states; #define IP_PORT_STATES(ipaddr) (port_states[ip]) #define PORT_22_INDEX 0 #define PORT_80_INDEX 1 // ...etc... /* some of the accessor macros */ #define PORT_STATE_MASK (0x00000003) #define PORT_STATE(ipaddr, port_index) \ (PORT_STATE_MASK & (IP_PORT_STATES(ipaddr) >> (3 * (port_index))) #define PORT_CLOSED 0 #define PORT_OPEN 1 // ...etc... /* example usage */ uint32 open_count = 0; uint32 ip = 1; do { if (PORT_STATE(ip, PORT_22_INDEX) == PORT_OPEN) { open_count++; } } while (ip < 0xffffffff) > future hires If they can't handle calling a couple macros over a uint64 array, I wouldn't recommend hiring them. > too large to fit in memory It's not necessarily in memory - the "old-timer" is using a memory mapped file. edit: bugfix