Ben Chuanlong Du's Blog

It is never too late to learn.

Hands on the Deque Collection in Python

Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

Tips and Traps

  1. A deque is implemented via the circular queue data structure and it has O(1) time complexity appending from both ends.

  2. Unlike list and tuple collections, a deque CANNOT be sliced!

Spark Issue: SIGBUS

Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

Symptoms

CalledProcessError: Command './pine' died with .

Possible Causes

SIGBUS (bus error) is a signal that happens when you try to access memory that has not been physically mapped . There are several …

Ubuntu Crashes When Opening Settings

Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

I encountered an issue with Ubuntu 20.04 on my machine. Ubuntu crashes when I try to open settings or video players. After searching online, it seems that the problem happens …

Spark Issue: Could Not Execute Broadcast in 300S

Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

Symptoms

Caused by: org.apache.spark.SparkException: Could not execute broadcast in 600 secs. You can increase the timeout for broadcasts via spark.sql.broadcastTimeout or disable broadcast join by setting …

How Much to Push for Functional Programming and Immutability

Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

Most new programming languages (such as Rust, Go, Kotlin, Scala, etc.) support functional programming style and have clear distinguishment on mutable vs immutable variables. So, is functional programming superior to imperative …