There’s a great MSR demo from 2012 that shows the effect of latency on the experience of using a tablet . If you don’t want to watch the three minute video, they basically created a device which could simulate arbitrary latencies down to a fraction of a millisecond. At 100ms (1/10th of a second), which is typical of…
Today I landed yet another small change to libcurl internals that further reduces the number of small mallocs we do. This time the generic linked list functions got converted to become malloc-less (the way linked list functions should behave, really). Instrument mallocs I started out my quest a few weeks ago by…
This post describes how to write a simple Hello world bootloader
This article aims to provide an overview of the Zend Virtual Machine, as it is found in PHP 7. This is not a comprehensive description, but I try to cover most of the important parts, as well as some of the finer details.
Last weekend I was playing around with a way to represent null-terminated UTF8 strings in Rust. Rather than just toying with it forever, I decided ...
On a summer's day a trip in a hot tube train is a dreadful experience, but how did we end up with such hot tube trains, and what's being done about it?
htop is a great tool but lacks good documentation. This article takes a visual and simple approach to explaining htop.
During some random discussion with my colleague today, I rediscovered an experiment I did quite some years ago: MP3 compression of image data. This is, feed raw 8-bit-per-pixel grayscale image data into an MP3 encoder, let it compress it, and decode the MP3 file again. After some conversion (the decoder will always…
APFS is not currently safe to use with names which might have Unicode normalisation issues – which means it is only safe with a limited ASCII character set.
For the last 3 years I worked on an application that runs on Google App Engine. It is a fascinating, unique piece of service Google is offering here. Unlike anything you’ll find elsewhere. This is my in-depth, personal take on it.
Today we’ll look at one of the most basic and the most often used methods from the Java library: System.currentTimeMillis() .
Benchmarks & Tips for Big Data, Hadoop, AWS, Google Cloud, PostgreSQL, Spark, Python & More...
Several holidays ago, I got a bee in my bonnet and wrote a fast JSON parser whose parsed AST fits in a single contiguous block of memory. The code was small and simple and the performance was generally on-par with RapidJSON, so I stopped and moved on with my life.
“iOS HFS Normalized UNICODE names, APFS now treats all files as a bag of bytes on iOS. We are requesting that Applications developers call the correct Normalization routines to make sure the file name contains the correct representation.”
ZFS should have been great, but I kind of hate it: ZFS seems to be trapped in the past, before it was sidelined it as the cool storage project of choice; it's inflexible; it lacks modern flash integration; and it's not directly supported by most operating systems. But I put all my valuable data on ZFS because it…
Jeff Atwood, perhaps the most widely read programming blogger, has a post that makes a case against using ECC memory . My read is that his major points are:
This is a pseudo-transcript for a talk on branch prediction given at Two Sigma on 8/22/2017 to kick off "localhost", a talk series organized by RC .
Typically, if you're designing a storage system - such as a filesystem, or a database - one of your major concerns is how to store the data on disk. You have to take care of allocating space for the objects to be stored, as well as storing the indexing data; you have to worry about what happens when you want to extend…
Now that the CoreCLR is open-source we can do fun things, for instance find out if it’s possible to add new IL (Intermediate Language) instruction to the runtime.
The log is a totally-ordered, append-only data structure. It’s a powerful yet simple abstraction—a sequence of immutable events. It’s something that programmers have been using for a very long time, perhaps without even realizing it because it’s so simple. Whether it’s application logs, system logs, or access logs…
Some notes on the different patterns that may be present when people talk about event-driven architectures.
