Category: Linux

Using signalfd and pidfd to make signals less painful under Linux

Anyone introduced to Unix programming gets to marvel at the clever construct of signals. In the life-cycle of a process, fortune and misfortune are present in good measure. Signals allow the operating system to tell the process about the occurrence of various events like the execution of illegal CPU instructions, a user typing and thus… Continue reading Using signalfd and pidfd to make signals less painful under Linux

Containers the hard way: Gocker: A mini Docker written in Go

They are popular and they are misunderstood. Containers have become the default way applications are packaged and run on servers, initially popularized by Docker. Now, Docker itself is misunderstood. It is the name of a company and a command (a suite of commands, rather) that allow you to manage containers (create, run, delete, network) easily.… Continue reading Containers the hard way: Gocker: A mini Docker written in Go

io_uring By Example: Part 3 – A Web Server with io_uring

This article is a part of a series on io_uring Series introduction Part 1: Introduction to io_uring. In this article we create cat_uring based on the raw io_uring interface and cat_liburing, built on the higher level liburing. Part 2: Queuing multiple operations: We develop a file copying program, cp_liburing leveraging multiple requests with io_uring. Part… Continue reading io_uring By Example: Part 3 – A Web Server with io_uring

io_uring By Example: Part 2 – Queuing multiple requests

This article is a part of a series on io_uring Series introduction Part 1: Introduction to io_uring. In this article we create cat_uring based on the raw io_uring interface and cat_liburing, built on the higher level liburing. Part 2: This article. Part 3: A web server written using io_uring. In part 1, we saw how… Continue reading io_uring By Example: Part 2 – Queuing multiple requests

io_uring by example: Part 1 – Introduction

This article is a part of a series on io_uring Series introduction Part 1: This article. Part 2: Queuing multiple operations: We develop a file copying program, cp_liburing leveraging multiple requests with io_uring. Part 3: A web server written using io_uring. Introduction Come to think about it, I/O, along with compute are the only two… Continue reading io_uring by example: Part 1 – Introduction

Sparkler: A KVM-based Virtual Machine Manager

[Join the discussion on Hacker News here.] Serverless computing is quite the rage these days and AWS Lambda is on the forefront of this. A while ago, they released Firecracker, the engine behind Lambda. Unsurprisingly, it was based on Linux’s KVM (Kernel-based Virtual Machine) technology, but what was surprising was how it gave up the… Continue reading Sparkler: A KVM-based Virtual Machine Manager

How AWS Firecracker works: a deep dive

Anything that powers technology like AWS Lambda needs to be really fast. And it needs to be secure. While AWS could have gone with existing technology, to satisfy both these main requirements, they went with building something new, Firecracker, that is both really fast – it can boot Linux and start executing user space processes… Continue reading How AWS Firecracker works: a deep dive

Linux Pressure Stall Information (PSI) by Example

[Discuss this article and read other’s comments on the subject on this thread on Hacker News.] The three fundamental building blocks of computers, CPU, I/O and RAM can come under pressure due to contention and this is not uncommon. To both accurately size workloads and to increase hardware utilization, having information on how much pressure… Continue reading Linux Pressure Stall Information (PSI) by Example