207. JIT Compilation with PyPy

---

🔹 1. Checking if Your Code is Running on PyPy

• Before optimizing, check if you are using PyPy.

import platform

if platform.python_implementation() == "PyPy":
    print("Running on PyPy!")
else:
    print("Not running on PyPy!")

🔍 How it works:

• platform.python_implementation() returns "PyPy" if PyPy is being used.

---

🔹 2. Simple Function Benchmark (CPython vs. PyPy)

• Measure the execution time of a loop in PyPy vs. CPython.

import time

def compute():
    total = 0
    for i in range(10**7):
        total += i
    return total

start = time.time()
compute()
end = time.time()

print("Execution time:", end - start)

🔍 How it works:

• The function runs faster on PyPy due to JIT optimizations.

---

🔹 3. Loop Optimization with PyPy JIT

• PyPy’s JIT compiler optimizes hot loops.

def optimized_loop(n):
    i, total = 0, 0
    while i < n:
        total += i
        i += 1
    return total

optimized_loop(10**7)  # Faster execution on PyPy

🔍 How it works:

• The JIT compiler recognizes patterns in loops and optimizes them dynamically.

---

🔹 4. Using __pypy__ Module for Extra Performance

• PyPy provides __pypy__ for extra optimizations.

import __pypy__

def efficient_list():
    return __pypy__.newlist_hint(10**6)  # Optimized list allocation

lst = efficient_list()
print(type(lst))  # Still a list but optimized

🔍 How it works:

• __pypy__.newlist_hint(size) optimizes list preallocation.

---

🔹 5. Faster Dictionary Lookups with __pypy__

• PyPy optimizes dictionary operations.

import __pypy__

d = __pypy__.newdict()
d["key1"] = "value1"
d["key2"] = "value2"

print(d["key1"])  # Fast access

🔍 How it works:

• __pypy__.newdict() creates a highly optimized dictionary.

---

🔹 6. Using PyPy for Faster Recursive Functions

• PyPy JIT-optimizes recursive calls better than CPython.

def factorial(n):
    if n == 0:
        return 1
    return n * factorial(n - 1)

print(factorial(500))  # Handles deep recursion efficiently

🔍 How it works:

• PyPy’s JIT reduces function call overhead, making recursion more efficient.

---

🔹 7. Faster String Concatenation in PyPy

• PyPy optimizes string operations.

def concat_strings(n):
    s = ""
    for i in range(n):
        s += str(i)  # CPython is slow, PyPy is optimized
    return s

concat_strings(10**5)  # Faster in PyPy

🔍 How it works:

• PyPy avoids repeated string allocations, making concatenation efficient.

---

🔹 8. Optimizing Integer Arithmetic

• PyPy uses optimized integer storage.

def sum_large_numbers(n):
    return sum(range(n))

print(sum_large_numbers(10**7))  # Faster integer operations

🔍 How it works:

• PyPy stores integers more efficiently and optimizes arithmetic.

---

🔹 9. Using NumPy with PyPy for Even Faster Performance

• PyPy speeds up NumPy array computations.

import numpy as np

a = np.arange(10**6)
b = np.arange(10**6)

c = a + b  # Fast computation
print(c[:5])  # First 5 elements

🔍 How it works:

• PyPy optimizes array operations by reducing memory overhead.

---

🔹 10. Comparing CPython vs. PyPy Performance

• Benchmarking both interpreters.

import time

def test_speed():
    total = 0
    for i in range(10**7):
        total += i
    return total

start = time.time()
test_speed()
end = time.time()

print("Execution time:", end - start)

🔍 How it works:

• Run the script in both CPython and PyPy to see the speed difference.

---

🚀 Why PyPy is Faster?

Feature	Benefit
JIT Compilation	Translates Python bytecode to machine code at runtime
Optimized Loops	Hot loops run at near C-speed
Better Memory Management	Reduces allocation overhead
Faster Function Calls	Optimized function execution
Efficient Integer Storage	Avoids Python object overhead

---

🚀 Running the Code in PyPy

• Install PyPy:

  sudo apt install pypy3  # Linux
  brew install pypy3      # macOS

• Run your script:

  pypy3 script.py

---

🚀 Final Thoughts

• PyPy’s JIT compiler speeds up Python code without changing it.

• Best for loops, recursion, string operations, and numeric computations.

• Try running these snippets in both CPython and PyPy to compare performance!