Day 460: 7/1/2026 Why Python Execution Is Slow? Python is expressive, flexible, and easy to use — but when performance matters, it often struggles. This is not because Python is “badly written,” but because of how Python executes code and accesses memory. Let’s break it down. ⚙️ 1. Python Works With Objects, Not Raw Data In Python, data is not stored contiguously like in C or C++. Instead: --> Each value is a Python object --> Objects live at arbitrary locations in memory --> Variables hold pointers to those objects When Python accesses a value: --> The pointer is loaded --> The CPU jumps to that memory location --> The Python object is loaded --> Metadata is inspected --> The actual value is read This pointer-chasing happens for every operation. 🔁 2. Python Is Interpreted, Not Compiled to Machine Code Python source code is not executed directly. Execution flow: --> Python source is compiled into bytecode --> Bytecode consists of many small opcodes --> The Python interpreter: fetches an opcode, decodes it, dispatches it to the corresponding C implementation --> This repeats for every operation --> Each step adds overhead. Even a simple arithmetic operation involves: --> multiple bytecode instructions --> multiple function calls in C --> dynamic type checks at runtime ⚠️ 3. Dynamic Typing Adds Runtime Checks Because Python is dynamically typed: --> Types are not known at compile time --> Every operation checks type compatibility --> Method lookups happen at runtime This flexibility makes Python powerful — but it prevents many low-level optimizations. Stay tuned for more AI insights! 😊 #Python #Performance #SystemsProgramming
Optimizing Python Performance: Understanding Execution and Memory Access
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Day 459: 6/1/2026 Why Python Objects Are Heavy? Python is loved for its simplicity and flexibility. But that flexibility comes with a cost — Python objects are memory-heavy by design. ⚙️ What Happens When You Create a Python Object? Let’s take a simple example: a string. When you create a string in Python, you are not just storing characters. Python allocates a full object structure around that value. Every Python object carries additional metadata. 🧱 1. Object Header (Core Overhead) Every Python object has an object header that stores: --> Type Pointer Points to the object’s type (e.g., str, int, list) Required because Python is dynamically typed Enables runtime checks like: which methods are valid whether operations are allowed This is why “a” + 1 raises a TypeError Unlike C/C++, Python must always know the object’s type at runtime. --> Reference Count Tracks how many variables reference the object Used for Python’s memory management When the count drops to zero, the object is immediately deallocated This bookkeeping happens for every object, all the time. 🔐 2. Hash Cache (For Immutable Objects) Immutable objects like strings store their hash value inside the object. Why? Hashing strings is expensive Dictionaries need fast lookups So Python caches the hash: Hash computed once Reused for dictionary and set operations Enables average O(1) lookups This improves speed — but adds more memory per object. 📏 3. Length Metadata Strings also store their length internally. This allows: len(s) to run in O(1) slicing and iteration without recomputing length efficient bounds checking Again: faster execution, but extra memory. Stay tuned for more AI insights! 😊 #Python #MemoryManagement #PerformanceOptimization
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Python devs, this one is a big deal 👀 If you’ve ever written a CPU-heavy Python script, watched only one core max out, and whispered “thanks, GIL” under your breath, this is for you. Python 3.12 quietly introduced something foundational for performance: Subinterpreters with per-interpreter GILs (PEP 684). What does that mean in practice? True parallelism for CPU-bound Python code Multiple interpreters inside a single process No heavyweight multiprocessing, no pickling overhead A real path toward multi-core Python without burning memory In my latest post, I walk through: Why the GIL has been the wall for years How subinterpreters change Python’s execution model An experimental example using _xxsubinterpreters Why this matters more right now than “GIL removal” headlines This is the groundwork for Python’s high-performance future — and it’s already here. 👉 Read the full breakdown here: https://lnkd.in/gcfsn2U3 Would love to hear how you’re thinking about concurrency in Python 👇 #Python #Python312 #PerformanceEngineering #Concurrency #BackendEngineering #SoftwareArchitecture #GIL #pythonInPlainEnglish
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How to Switch to ty from Mypy Python has supported type hinting for quite a few versions now, starting way back in 3.5. However, Python itself does not enforce type checking. Instead, you need to use an external tool or IDE. The first, and arguably the most popular, is mypy. Microsoft also has a Python type checker that you can use in VS Code called Pyright, and then there’s the lesser-known Pyrefly type checker and language server. The newest type checker on the block is Astral’s ty, the maker of Ruff. Ty is another super-fast Python utility written in Rust. In this article, you will learn how to switch your project to use ty locally and in GitHub Actions… https://lnkd.in/d3i-mgnq
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Day 464: 11/1/2026 Why Python Exceptions Are Expensive? --> Python exceptions are great for error handling. --> They are not cheap and using them in performance-critical paths can seriously hurt runtime. --> This isn’t an opinion. --> It’s a consequence of how Python executes code. Let’s break it down. ⚙️ 1. Exceptions Are Not Simple Control Flow In Python, an exception is not just a conditional jump. Raising an exception triggers: --> stack unwinding --> frame inspection --> object creation --> metadata propagation This is orders of magnitude more expensive than an if check. Exceptions are designed for rare events, not normal execution paths. 🧱 2. Exception Objects Are Real Python Objects When an exception is raised, Python creates: --> an exception object --> a traceback object --> references to stack frames Each of these: --> allocates memory --> updates reference counts --> stores metadata Even if the exception is immediately caught, this work already happened. 🔁 3. Stack Unwinding Is Costly To raise an exception, Python must: --> walk up the call stack --> identify the correct except block --> clean up intermediate frames --> restore execution state This process touches multiple stack frames and Python objects. In deep call stacks, this cost increases further. 🧠 4. Tracebacks Are Expensive by Design Tracebacks store: --> file names --> line numbers --> function names --> execution context This is extremely useful for debugging but it means exception handling prioritizes diagnostics over speed. Stay tuned for more AI insights! 😊 #Python #PerformanceOptimization #SoftwareEngineering
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Python didn’t become one of the most widely used programming languages by accident. Its history is a story of deliberate design choices: readability over cleverness, practicality over theory, and a strong community over hype. Looking back at how Python evolved helps explain why it’s still a go-to language for modern software, data, and AI systems. 👉 Read the full story here: The History of Python Programming Language: How It All Began (https://lnkd.in/eu_PPKHz)
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Day 461: 8/1/2026 Why Python Strings Are Immutable? Python strings cannot be modified after creation. At first glance, this feels restrictive — but immutability is a deliberate design choice with important performance and correctness benefits. Let’s break down why Python does this. ⚙️ 1. Immutability Enables Safe Hashing Strings are commonly used as: --> dictionary keys --> set elements --> For this to work reliably, their hash value must never change. If strings were mutable: --> changing a string would change its hash --> dictionary lookups would break --> internal hash tables would become inconsistent By making strings immutable: --> the hash can be computed once --> cached inside the object --> reused safely for O(1) lookups This is a foundational guarantee for Python’s data structures. 🔐 2. Immutability Makes Strings Thread-Safe Immutable objects: --> cannot be modified --> can be shared freely across threads --> require no locks or synchronization This simplifies Python’s memory model and avoids subtle concurrency bugs. Even in multi-threaded environments, the same string object can be reused safely without defensive copying. 🚀 3. Enables Memory Reuse and Optimizations Because strings never change, Python can: --> reuse string objects internally --> safely share references --> avoid defensive copies Example: --> multiple variables can point to the same string --> no risk that one modification affects another This reduces: --> memory usage --> allocation overhead --> unnecessary copying 🧠 4. Predictable Performance Characteristics Immutability allows Python to store: --> string length --> hash value --> directly inside the object. As a result: --> len(s) is O(1) --> hashing is fast after the first computation --> slicing and iteration don’t need recomputation --> This predictability improves performance across many operations. Stay tuned for more AI insights! 😊 #Python #Programming #Performance #MemoryManagement
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Python 3.14 keeps raising the bar for developer productivity : clearer errors, smarter templates(t-strings) and serious progress toward parallel execution. Small changes, big long-term impact.
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🔐 Understanding Python’s GIL (in simple terms) If you’ve ever heard “Python doesn’t scale with threads”, the reason is usually the GIL. GIL (Global Interpreter Lock) is a rule in CPython that says: 👉 Only one thread can execute Python code at a time. Think of it like this 👇 You have one whiteboard (Python interpreter) and multiple people (threads). Even if everyone is ready to write, only one person can use the marker at any moment. 🧠 Why does Python do this? Python uses a simple memory management system. The GIL keeps things safe and fast for single-threaded code, but limits parallel execution. 📌 What does this mean in practice? ❌ CPU-heavy tasks (calculations, loops) don’t get faster with threads ✅ I/O-heavy tasks (API calls, DB queries, file reads) do benefit from threads Why? Because during I/O, Python waits, and the GIL is released for other threads. 🚀 How developers work around GIL Use multiprocessing (multiple processes, multiple GILs) Use NumPy / Pandas (they release GIL internally) Use async for I/O-heavy workloads 🎯 Key takeaway GIL doesn’t make Python slow — it makes it predictable. The trick is choosing the right concurrency model.
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If you’ve ever found yourself stuck in loop-heavy Python code, this one’s for you 🙂 While learning Python, I realized that many problems I was solving with long for loops could be written in a much cleaner and more expressive way using higher-order functions. I’ve shared this learning in a Medium article 📖 Beyond Loops: Leveraging Higher-Order Functions in Python ✔️ What I cover: > map(), filter(), lambda, reduce() > When to use them (and why it matters) > Easy-to-follow examples Writing this helped me better understand how thinking functionally can simplify everyday Python problems. I am really grateful to Harsha Mg for his support and feedback. 👉 Check it out here: https://lnkd.in/gefA4VEm 💬 I’d love to know — do you usually prefer traditional for loops, or higher-order functions in Python? #Python #HigherOrderFunctions #map() #reduce() #filter() #lambda #MediumBlog #InnomaticsResearchLabs
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Ever wonder how much memory an empty list takes? How about how long it takes to add two integers in Python? How fast is adding an element to a Python list? How does that compare to opening a file does it usually take less than a millisecond? Are there hidden factors that make these operations slower than expected? When writing performance-sensitive code, which data structures are most appropriate? How much memory does a floating-point number consume in Python? What about a single character or an empty string? Came across a great write-up on this👇 https://lnkd.in/gdWieZhY
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