What if your open the same file in several processes and you write to it simultaneously? What is the result? Do these process share the same file offset when they try to write? What about writing to the same file in the same process using different threads?(Take Linux for example.)

Even though it is impossible to ignore how databases work, the problems that application developers foresee and experience will often be just the tip of the iceberg. In this series, she share a few insights that useful for developers who are not specializeed in database domain.

…and how we rewrote the heart of sync with confidence. On same topic of testing large scale system, you can also checkout How Vector, an log pipeline system like FluentD/LogStash, test their system

needless to say, many will encounter this. We started small, using this provider, then move to AWS, or found that AWS is too expensive, and move out. The primary point is using an intermediate server to replicate data.

Line is a messaging app. They have crazy spike on December 31st when users share New Year’s greeting. They shares their effort to prepare for these spikes. How they write benchmark tool, prepare visualization to see the difference.

TCP is supposed to guarantee that all bytes sent by one endpoint of a connection will be received, in the same order, by the other endpoint. In this article we’ll identify and demonstrate a wrinkle in the Linux implementation of TCP SYN cookies. The client can connect and send two packets, but the server’s TCP stack delivers the data in the second packet to the application, unaware that it is not the first packet in the stream.

The article also contains lot of link to other tool such as AWS Firewall Manager, Security Hub, Guard Duty to help you secure your AWS account. I usually won’t link to these list of tooling articles but on second though I think it’s indeed useful and provide real value

This is part of a self-published book project by Balthazar Rouberol and Etienne Brodu. If you spend a good chunk of your day repeatedly hitting the left and right arrow keys to navigate in long commands or correct typos, or hitting the up or down arrow keys to navigate your command history, this chapter should help you get more done quicker.

DNS is a globally distributed hierarchical database that maps domain names to Internet hosts throughout the world. It evolve using a single HOSTS.txt file to map domain to ip address. The DNS distributed database is an inverted tree indexed by domain names. Taken together, the entire tree is called the domain namespace and represents the entire set of Internet domain names.

A short tip to find out where a Postgres config is definied. Is it from environment variable, from config file, store inside system table?

Dashbit has been monitoring 100,000’s of serverless backend components for 2+ years at Dashbird. In their experience, Serverless infrastructure failures boil down to: 1) Throughput and concurrency limitations. 2) Increased latency; 3) Timeout errors.

This cheat sheet offers an overview of current security best practices for developers building OAuth 2.x client applications

Ever forgot the name of a tool and have to search your own note, do some quick google? Well, this note has all of them. Also, another tool is the Linux proc file system can be used to troubleshoot