Text Processing (Grep/Sed/Awk)

Stop struggling with massive CSV files that break your memory

🧩 The Challenge

Dealing with a multi-gigabyte CSV file on a server that only has a few gigs of RAM is a recipe for a kernel panic. I’ve spent way too long waiting for an editor to load only for the system to lock up solid.

💡 The Fix

Use awk to pull only the specific columns you need without loading the entire file into memory. It treats the file like a stream, so you never overflow your buffer.

awk -F',' '{print $3, $7}' giant_report.csv > filtered_output.txt

⚙️ Why It Works

By default, awk processes line by line, meaning it only keeps one record in memory at any given time. This keeps the load off your system RAM regardless of how large the input file gets.

🚀 Pro-Tip: Use the -v OFS=’,’ flag if you need the output to remain a valid CSV with a specific delimiter.

Linux Tips & Tricks | © ngelinux.com | 8/23/2026