Himeno and C-Ray are two more test cases heavily favoring 64-bit Ubuntu over 32-bit Ubuntu even when run from an old Mac Mini with Intel Core 2 Duo and just 1GB of system memory.
To no surprise compared to our 32-bit vs. 64-bit benchmarking over nearly the past decade on Phoronix, the 64-bit version of Ubuntu generally delivers superior performance over 32-bit Ubuntu. This strong 64-bit performance is even when using an old Intel Core 2 Duo system with just 1GB of memory. The reasons for avoiding 64-bit Linux are generally moot these days with Flash, Java, and other applications now running just fine on x86_64 distributions. The state of multi-lib on Ubuntu and other Linux distributions is also in good standing.