The x86_64 Linux kernel can handle a maximum of 4096 Processor threads in a single system image. This means that with hyper threading enabled, the maximum number of processor cores is 2048.

Does Linux support multiple cores?

Linux kernel supports multicore CPUs, therefore Ubuntu does as well. The “optimization” is given by the quality level of this “support”. If you want the most performance, you might want to run the 64-bit version of Ubuntu which may sometime be faster in some tasks.

How many cores can Ubuntu use?

The Ubuntu kernel is configured to support 8 processors / cores in 32-bit and 64 processors / cores in 64-bit.