Full Width [alt+shift+f] Shortcuts [alt+shift+k]
Sign Up [alt+shift+s] Log In [alt+shift+l]
Articles [alt+h] Reading List [alt+r] [alt+s]

Evan Jones - Software Engineer | Computer Scientist

Visit Blog

Sort By

Popular [alt+1] Recent [alt+2]

Change View

List View [alt+w] Expanded [alt+e]
Evan Jones -...
The C Standard Library Function isspace() Depends on Locale This is a post for myself, because I wasted a lot of time understanding this bug, and I want to be...
a year ago
68

The C Standard Library Function isspace() Depends on Locale

from Evan Jones - Software Engineer | Computer Scientist [alt+shift+b] in programming

a year ago
This is a post for myself, because I wasted a lot of time understanding this bug, and I want to be able to remember it in the future. I expect close to zero others to be interested. The C standard library function isspace() returns a non-zero value (true) for the six "standard"...
Direct Link [→] Remove from reading list Add to reading list [alt+a]
upvote [alt+ctrl+↑] downvote [alt+ctrl+↓]
Evan Jones -...
How much does the read/write buffer size matter for socket throughput? The read() and write() system calls take a variable-length byte array as an argument. As a...
a year ago
59

How much does the read/write buffer size matter for socket throughput?

from Evan Jones - Software Engineer | Computer Scientist [alt+shift+b] in programming

a year ago
The read() and write() system calls take a variable-length byte array as an argument. As a simplified model, the time for the system call should be some constant "per-call" time, plus time directly proportional to the number of bytes in the array. That is, the time for each call...
Direct Link [→] Remove from reading list Add to reading list [alt+a]
upvote [alt+ctrl+↑] downvote [alt+ctrl+↓]
Evan Jones -...
Huge Pages are a Good Idea Nearly all programs are written to access virtual memory addresses, which the CPU must translate to...
over a year ago
33

Huge Pages are a Good Idea

from Evan Jones - Software Engineer | Computer Scientist [alt+shift+b] in programming

over a year ago
Nearly all programs are written to access virtual memory addresses, which the CPU must translate to physical addresses. These translations are usually fast because the mappings are cached in the CPU's Translation Lookaside Buffer (TLB). Unfortunately, virtual memory on x86 has...
Direct Link [→] Remove from reading list Add to reading list [alt+a]
upvote [alt+ctrl+↑] downvote [alt+ctrl+↓]
Evan Jones -...
TCP and gRPC Failed Connection Timeouts After my last article about how gRPC is hard to configure, with a client keepalive example, I...
over a year ago
31

TCP and gRPC Failed Connection Timeouts

from Evan Jones - Software Engineer | Computer Scientist [alt+shift+b] in programming

over a year ago
After my last article about how gRPC is hard to configure, with a client keepalive example, I realized that I don't understand how TCP and gRPC handle failed connections. This article is my attempt to figure it out, and document it so I can find it again in the future. The best...
Direct Link [→] Remove from reading list Add to reading list [alt+a]
upvote [alt+ctrl+↑] downvote [alt+ctrl+↓]
Evan Jones -...
Replicating Database Changes to a Message Queue is Tricky Let's imagine we have an program that stores its state in a database, and we want other programs to...
over a year ago
30

Replicating Database Changes to a Message Queue is Tricky

from Evan Jones - Software Engineer | Computer Scientist [alt+shift+b] in programming

over a year ago
Let's imagine we have an program that stores its state in a database, and we want other programs to do things when changes occur. For example, we might want to send email notifications if a bank balance drops below a threshold. This is a very common reason applications use...
Direct Link [→] Remove from reading list Add to reading list [alt+a]
upvote [alt+ctrl+↑] downvote [alt+ctrl+↓]
Evan Jones -...
Setenv is not Thread Safe and C Doesn't Want to Fix It You can't safely use the C setenv() or unsetenv() functions in a program that uses threads. Those...
a year ago
29

Setenv is not Thread Safe and C Doesn't Want to Fix It

from Evan Jones - Software Engineer | Computer Scientist [alt+shift+b] in programming

a year ago
You can't safely use the C setenv() or unsetenv() functions in a program that uses threads. Those functions modify global state, and can cause other threads calling getenv() to crash. This also causes crashes in other languages that use those C standard library functions, such as...
Direct Link [→] Remove from reading list Add to reading list [alt+a]
upvote [alt+ctrl+↑] downvote [alt+ctrl+↓]
Evan Jones -...
Postgres large sub-string query performance Following up on my last post about large JSON queries, I also benchmarked sub-string queries on...
over a year ago
29

Postgres large sub-string query performance

from Evan Jones - Software Engineer | Computer Scientist [alt+shift+b] in programming

over a year ago
Following up on my last post about large JSON queries, I also benchmarked sub-string queries on large variable-length strings. I wanted to check if sub-string queries might be faster than HSTORE or JSONB key lookups. I tested both binary (BYTEA) and Unicode text (TEXT)....
Direct Link [→] Remove from reading list Add to reading list [alt+a]
upvote [alt+ctrl+↑] downvote [alt+ctrl+↓]
Evan Jones -...
Go: Functional options are slow The Go "functional options" pattern is a way of passing options to a function. The function takes a...
over a year ago
27

Go: Functional options are slow

from Evan Jones - Software Engineer | Computer Scientist [alt+shift+b] in programming

over a year ago
The Go "functional options" pattern is a way of passing options to a function. The function takes a variable number of arguments, which are themselves functions (a type like ...func(*config). I think it was first introduced by Rob Pike in a 2014 blog post. It is now used by many...
Direct Link [→] Remove from reading list Add to reading list [alt+a]
upvote [alt+ctrl+↑] downvote [alt+ctrl+↓]
Evan Jones -...
Network Latencies in the Data Center Jeff Dean used to do a talk that included "Numbers Everyone Should Know" (2007 at Stanford, 2009 at...
over a year ago
26

Network Latencies in the Data Center

from Evan Jones - Software Engineer | Computer Scientist [alt+shift+b] in programming

over a year ago
Jeff Dean used to do a talk that included "Numbers Everyone Should Know" (2007 at Stanford, 2009 at LADIS), which included "round trip within same data center" as 500 us. I was recently wondering if that is still true, and more importantly what does the distribution of latencies...
Direct Link [→] Remove from reading list Add to reading list [alt+a]
upvote [alt+ctrl+↑] downvote [alt+ctrl+↓]
Evan Jones -...
Advice on looking for a new software engineering job I've been working professionally as a software engineer since 2006, which means I've been doing this...
over a year ago
25

Advice on looking for a new software engineering job

from Evan Jones - Software Engineer | Computer Scientist [alt+shift+b] in programming

over a year ago
I've been working professionally as a software engineer since 2006, which means I've been doing this long enough that people now ask me for advice. I've only changed jobs 3 times in my career, so I'm not sure I'm an expert. However, I decided I should write down my advice, to...
Direct Link [→] Remove from reading list Add to reading list [alt+a]
upvote [alt+ctrl+↑] downvote [alt+ctrl+↓]
Evan Jones -...
Postgres large JSON value query performance Postgres supports three types for "schemaless" data: JSON (added in 9.2), JSONB (added in 9.4), and...
over a year ago
25

Postgres large JSON value query performance

from Evan Jones - Software Engineer | Computer Scientist [alt+shift+b] in programming

over a year ago
Postgres supports three types for "schemaless" data: JSON (added in 9.2), JSONB (added in 9.4), and HSTORE (added in 8.2 as an extension). Unfortunately, the performance of queries of all three gets substantially slower (2-10×) for values larger than about 2 kiB, due to how...
Direct Link [→] Remove from reading list Add to reading list [alt+a]
upvote [alt+ctrl+↑] downvote [alt+ctrl+↓]
Evan Jones -...
Getting $3300 from a casino promotion New York State legalized mobile sports gambling in January 2022. The casinos offered crazy...
over a year ago
24

Getting $3300 from a casino promotion

from Evan Jones - Software Engineer | Computer Scientist [alt+shift+b] in programming

over a year ago
New York State legalized mobile sports gambling in January 2022. The casinos offered crazy promotions to get people signed up. The craziest offered $3300 of free money. I did the math, and there was a low risk way to claim this money. As long as you placed 11 or more bets, you...
Direct Link [→] Remove from reading list Add to reading list [alt+a]
upvote [alt+ctrl+↑] downvote [alt+ctrl+↓]
Evan Jones -...
gRPC is easy to misconfigure Google's gRPC is an RPC system that supports many languages, and is relatively widely used. I think...
over a year ago
22

gRPC is easy to misconfigure

from Evan Jones - Software Engineer | Computer Scientist [alt+shift+b] in programming

over a year ago
Google's gRPC is an RPC system that supports many languages, and is relatively widely used. I think its popularity is due to being used for parts of Docker and Kubernetes. I think gRPC is mostly fine, but it is surprisingly easy to screw up by misconfiguring it. Part of that is...
Direct Link [→] Remove from reading list Add to reading list [alt+a]
upvote [alt+ctrl+↑] downvote [alt+ctrl+↓]
Evan Jones -...
Random Load Balancing is Unevenly Distributed This is a reminder that random load balancing is unevenly distributed. If we distribute a set of...
a year ago
18

Random Load Balancing is Unevenly Distributed

from Evan Jones - Software Engineer | Computer Scientist [alt+shift+b] in programming

a year ago
This is a reminder that random load balancing is unevenly distributed. If we distribute a set of items randomly across a set of servers (e.g. by hashing, or by randomly selecting a server), the average number of items on each server is num_items / num_servers. It is easy to...
Direct Link [→] Remove from reading list Add to reading list [alt+a]
upvote [alt+ctrl+↑] downvote [alt+ctrl+↓]
Evan Jones -...
Nanosecond timestamp collisions are common I was wondering: how often do nanosecond timestamps collide on modern systems? The answer is: very...
a year ago
16

Nanosecond timestamp collisions are common

from Evan Jones - Software Engineer | Computer Scientist [alt+shift+b] in programming

a year ago
I was wondering: how often do nanosecond timestamps collide on modern systems? The answer is: very often, like 5% of all samples, when reading the clock on all 4 physical cores at the same time. As a result, I think it is unsafe to assume that a raw nanosecond timestamp is a...
Direct Link [→] Remove from reading list Add to reading list [alt+a]
upvote [alt+ctrl+↑] downvote [alt+ctrl+↓]

The best way to read the internet.
Made for nerds, by a nerd.

The best way to read the internet

© 2023 Bored Reading. All rights reserved.

Terms Privacy Design by Kumail

bored reading

v. 229.328 compliant with
earth/mars-x8292 communication
protocol 29xjw899992

When Google killed Google Reader, the bloggosphere took a severe hit and the content quality went down because there weren't enough readers to justify the effort it takes to maintain a high quality blog.

What's left is a decaying wasteland of blogs, most abandoned, a lot are now SEO spam, and 99% are not worth reading. BoredReading is a way to read the remaining great blogs that survived the ice age.

To add your favorite blog, please suggest it here! I get emails every day which helps me maintain a high quality selection of blogs!

Avatar

Made by,
Kumail Hunaid

@kumailht on Twitter.
My website and email.

Close [esc]