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This is fun and all, but the benchmarks here aren't really what the author seems to think they are. This isn't "computationally expensive", the script is basically only control flow, where the CPU spend more time doing variable lookups than the actual computation. This means most of the pipeline width sits completely unused, whcih is a pretty large disservice to the M1 and the i5. There's also no control for the ther…
2GB Pi is $55 on amazon. 4GB version is $62. That'd be $450+ for the eight pies. Ryzen 2700 launched at $300 (and tapered down to ~$200) and would pretty much run circles around such a Pi cluster. Just saying. These Pi clusters can be a cool and fun thing to build but if you're looking for compute power, you'd be better served by a mid-range desktop.
2GB pi starts at $35 at actual Raspberry Pi distributors, 4GB at $55, although there will probably be added shipping cost.
For my region, the actual distributors start at 44 EUR for 2GB and 64 EUR for 4GB.
10,000: 0.52 seconds.
100,000: 41.48 seconds.
200,000: 157.68 seconds.
This is fun and all, but the benchmarks here aren't really what the author seems to think they are. This isn't "computationally expensive", the script is basically only control flow, where the CPU spend more time doing variable lookups than the actual computation. This means most of the pipeline width sits completely unused, whcih is a pretty large disservice to the M1 and the i5. There's also no control for the ther…
There's no mention of M1 in the article
Please redo the benchmark against the M1.
I tried FindingPrimesMulti.py on a 3970x: Find all primes up to: 10000 using 256 processes. Time elasped: 0.51 seconds Number of primes found 1229 Find all primes up to: 100000 using 256 processes. Time elasped: 36.71 seconds Number of primes found 9592 Find all primes up to: 200000 using 256 processes. Time elasped: 149.55 seconds Number of primes found 17984 EDIT: ran it again: Find all primes up to: 200000 using 2…
2GB Pi is $55 on amazon. 4GB version is $62. That'd be $450+ for the eight pies. Ryzen 2700 launched at $300 (and tapered down to ~$200) and would pretty much run circles around such a Pi cluster. Just saying. These Pi clusters can be a cool and fun thing to build but if you're looking for compute power, you'd be better served by a mid-range desktop.
As always, a benchmark is the only thing that will prove it.
There are only 1229 primes up to 10,000, not 1230 as the article says. Not sure whether this is a bug in the code or a typo in the article. I still remember this because 25 years ago as a teenager I spend quite some time making primality testing as fast as I could. My implementation was certainly not as naive as the one from the article - only testing up to the square root of n, only testing against primes I had foun…
1 is considered prime by some.
#0 and 1 are not primesEarlier quoted context omitted.
There are also people who consider the world to be flat though. There is a very thorough mathematical definition of prime numbers and 1 is not prime according to that definition.
The definition a prime number is having two factors. As the multiplicative identity, one only has one factor. Some might see primes as being numbers with >=2 factors. This interpretation is less useful. What is completely useless is a definition that makes exclusions of specific numbers as dogma. What does that say about anything? It’s totally arbitrary and unexplanatory.