There are many benchmarks available to analyze the performance of our mobile phone. However, there is one very curious one that has been used for a long time in the world of computing: calculating the number Pi en different levels of complexity from the smartphone. The time it takes to calculate it gives us an idea of... the capacity of our Android mobile for CPU and memory intensive tasks.
Calculating the number Pi
Pi is an irrational numberWe usually know it as 3,14 or 3,1416, although it is still a approachBeing irrational, It has infinite decimal placesToday we know how to calculate more and more digits of Pi, but we need a processor that executes the algorithms accurately and quickly so that it is useful as a performance test. For example, a current mobile phone can calculate thousands of digits of Pi in fractions of a second, although depends on the model and its thermal management.
Comparing the performance of the Android mobile
With the Super Pi app, you can use your mobile phone to calculate the number Pi. For everyday use, it's It's useless to know so many decimal placesBut it's practical for comparing performance: depending on the time it takes the mobile to calculate PiYou'll get a reference point for your Android's performance. The app lets you choose between 8 thousand, 16 thousand, 32 thousand and so on 4 million digits (In the original text it appeared as bits, we have corrected it here). My mobile It took about 77 seconds in performing this last calculation.
If you like math and want compare the performance of various mobilesIt's a curious way of doing it. Super Pi It's free and very simple. It's not a comprehensive benchmark that measures all areas of performance, but it is a measurement. easy to replicate to compare devices and have a laugh with friends.
Pi calculation algorithms and what they actually measure
Behind every calculation of Pi there is very different algorithms with varying impacts on CPU and memory. Some advanced apps include options such as:
- AGM + FFT (Arithmetic-geometric mean + FFT): one of the most Quick for millions of digits. It is usually run on native C++ codeIt consumes a lot of memory on a large scale and works in powers of 2Therefore, 10 million digits can take about the same time as 16 million, depending on the internal precision.
- Machin's Formula: plus slow than AGM+FFT, but it shows the digits appearing in real timeIt is usually implemented in Java using BigDecimal. Processing times increase significantly when dealing with hundreds of thousands of digits.
- nth digit: algorithms such as those of Gourdon allow to calculate decimals in the middle without the above using very little memory. For positions less than 50 digits, variants such as the following are used: BellardThey are fast, but they don't outperform AGM+FFT when you want many millions of digits.
Keep in mind that, in many cases, these tests exercise single core to ensure consistency and isolate latencies. If your goal is to compare single-threaded CPUIt's perfect; if you're looking to measure multicoreYou will need other additional tests.
Tips for accurate measurements and reliable times
- Avoid the heatRun the tests with the phone cold and without a case. thermal throttling It can significantly slow down the results.
- Close apps and services: Free up RAM, enable airplane mode if you don't need it, and run in stable conditionsRepeat the test and average the results.
- Take care of the batteryKeep your battery above 50% and disable power saving modes. Some apps allow this. calculate with the screen offUseful for long calculations, but consumes battery.
- Choose the optimal size: 1 million digits is a good reference to compare; from certain thresholds the the memory It may be the limiting factor.
Limits, warnings and battery
The intensive calculation of Pi can drain the battery quicklyAt very large numbers, your device can losing memorytake a very long time or even close the appThere are no "hard" limits that are the same for everyone: they depend on you. CPU, memory and systemIf you notice instability, reduce the number of digits. For a precise timingIt prevents other apps from running in the background and makes sure the device doesn't get hot.
Where does Pi rank among the benchmarks?
Calculating Pi is a synthetic benchmark: generates a controlled mathematical load to measure computing speed and numerical efficiency. It complements, but does not replace, the application benchmarks (for example, video encoding, web browsing, 3D rendering) that evaluate real scenariosIn addition, some manufacturers optimize how the system responds to concrete processes...activating maximum performance modes. That's why it's useful to interpret Pi as a reference more within a set of tests.
Ideas for having fun with Pi
Beyond the total time, some tools let you look for patterns in the digits: your , famous sequences such as the Feynman Point (six consecutive nines in position 762) and other curiosities. For these searches to be useful, calculate at least one million digits.
Using Pi as a "power test" for your phone is simple, replicable, and even fun. If you're feeling adventurous, combine Super Pi times with other CPU, GPU, and storage tests for a more comprehensive analysis. more complete photograph of your Android's actual performance.
