Linus, father of Linux, said: parallel computing is basically a waste of time.

Linus, father of Linux, said: parallel computing is basically a waste of time.

 

This article is translated from a recent post by linus torvalds, the father of Linux.

What are the advantages of parallel computing?

The performance of the hardware cannot be improved forever. The current trend actually tends to reduce power consumption. So what are the benefits of promoting parallel technologies? We already know that proper out-of-order CPU is necessary, because people need reasonable performance, and out-of-order execution has proved to be more efficient than sequential execution.

Advocating the so-called "Parallel" greatly wastes everyone's time. The idea of "more efficient parallel processing" is purely nonsense. Large-capacity cache can improve efficiency. It is meaningless to perform parallel operations on some microkernels without cache, unless it is for a large number of rule operations ).

No one will go back to the past. The complex unordered running kernel will not disappear. Expansion won't keep going. What people need is mobility, so those who want to expand to hundreds of kernels are crazy, don't miss them.

How are they imagining how magical parallel algorithms can be used?

Parallelism is only meaningful to graphics computing and servers, and we have already applied a large number of parallel applications in these fields. It makes no sense to promote parallel applications to other fields.

So forget parallelism. It will not come. There are no problems with about four kernels for end users. In the mobile field, you cannot insert more cores without greatly increasing energy consumption. No rational person Will Caster the kernel to reduce its size and performance in order to keep it into more kernels. The only reason for caressing the kernel is that you want to further reduce power consumption, therefore, you still won't get a lot of cores.

Therefore, the argument about whether to pay attention to Program parallelism is simply a fallacy, and its prerequisites are all wrong. It is just an outdated buzzword.

Parallel Programs are useful in some of the areas mentioned above and have been widely used. For example, in the server field, people have been parallel for many years.

In other fields, parallelism is not essential, even in some unknown fields in the future, because you cannot. If you want to do low-power universal computer vision, I can basically ensure that you do not use the universal graphics processor GP CPU ). You don't even use a graphics processor because it consumes too much power. You may probably use special hardware based on some neural networks.

Give up. Parallel is the future.

Linus