Channel is usually used together with goroutines. Let’s take an example from k8s source code. This function returns a channel for callers to consume. Inside, it spawns a background goroutine to sen...

Many tools pg_ha_migrations for Ruby on Rails. The core part is this function. It acquires the lock beforehand. Basically, it first waits until no conflicting transaction exits. Then, it acquires ...

Q1. What plan contains? How is it executed? You know what? The part I love most about Postgres codebase is its comments. Very informative and I learned a lot from them. What does a query planner ...

Postgres official documentation Chapter 55. Frontend/Backend Protocol covers all the details about the client-sever binary protocol, which is a based on top of TCP. All communication is through...

WAL (Write Ahead Log) Tree locations postgres=# select pg_current_wal_flush_lsn(), pg_current_wal_lsn(), pg_current_wal_insert_lsn(); pg_current_wal_flush_lsn | pg_current_wal_lsn | pg_current_w...

RMI (Remote Method Invocation) RMI is a way of calling methods on remote objects over a network connection. It is similar to RPC, but the biggest difference is that RPC deals with data structures ...

When using GCC to add breakpoint to a specific location, sometimes I am worried that this piece of code may be optimized away by the compiler. Disabling optimization can rule out my concern, but I ...

I spent quite some time today debugging a seemingly trivial problem when working with Python ThreadPoolExecutor. The code is as follows. with concurrent.futures.ThreadPoolExecutor(max_workers=8) a...

Increase the disk size of StatefulSet PVC kubectl edit pvc <pvc-name> -n <namespace> kubectl delete statefulset --cascade=orphan <statefulset_name> -n <namespace> # Then yo...

I took a deep breath when starting this blog post. Lisp is such an arcane programming language. I am not sure I will benefit from it at all. However, since pgloader is written in CL, I think I shou...