Ok. Ideally assuming your threads do not have locking such that they do not block each other (independent of each other) and you can assume that the work load (processing) is same, then it turns out that, have a pool size of Runtime.getRuntime().availableProcessors() or availableProcessors() + 1 gives the best results. But say, if threads … Read more
There’s a crate to do this: num_cpus. References: crates.io page github.com source Add this to your Cargo.toml: [dependencies] num_cpus = “1.0” Then in your source: extern crate num_cpus; let num = num_cpus::get();
Yes, a hart is a hardware thread.
You can ask for as many processes as you like. Any limit that may exist will be imposed by your operating system, not by multiprocessing. For example, p = multiprocessing.Pool(1000000) is likely to suffer an ugly death on any machine. I’m trying it on my box as I type this, and the OS is grinding … Read more
http://play.golang.org/p/cuaf2ZHLIx package main import ( “fmt” “runtime” ) func main() { fmt.Println(runtime.NumCPU()) }
Processes vs Threads In days of old, each process had precisely one thread of execution, so processes were scheduled onto cores directly (and in these old days, there was almost only one core to schedule onto). However, in operating systems that support threading (which is almost all moderns OS’s), it is threads, not processes that … Read more
Yes. To quote MDN: The navigator.hardwareConcurrency read-only property returns the number of logical processors available to run threads on the user’s computer… Modern computers have multiple physical processor cores in their CPU (two or four cores is typical), but each physical core is also usually able to run more than one thread at a time … Read more
You can determine the number of processes available to the Java Virtual Machine by using the static Runtime method, availableProcessors. Once you have determined the number of processors available, create that number of threads and split up your work accordingly. Update: To further clarify, a Thread is just an Object in Java, so you can … Read more
The answer revolves around the purpose of threads, which is parallelism: to run several separate lines of execution at once. In an ‘ideal’ system, you would have one thread executing per core: no interruption. In reality this isn’t the case. Even if you have four cores and four working threads, your process and it threads … Read more
There are several different pieces of information relating to processors that you could get: Number of physical processors Number of cores Number of logical processors. These can all be different; in the case of a machine with 2 dual-core hyper-threading-enabled processors, there are 2 physical processors, 4 cores, and 8 logical processors. The number of … Read more