Technical Guide Eight Minutes for zgrep, Every Single Time — Keeping Logs Compressed and Still Searchable
[Update, 16 October 2026] Speed today — compressed logs can now be searched as-is, even in the free app The uv…
Technical Guide
Technical Guide 
Technical Guide Chasing an Outage by the Clock — Four Ways to Use Timestamps as Evidence
All you have is 14:07. That's the whole report. No error message, no request ID, no reproduction steps. A few…
Technical Guide The First Hours of an Intrusion Investigation — Four Steps Through Tens of Millions of Auth Log Lines
4,812 failures. One success. All from the same IP. It could be an attack, or someone who forgot their password…
Technical Guide The Day printf Debugging Hit 10GB — Four Ways to Live With Development Logs
10GB, waiting for me in the morning. It came from one printf I dropped into a loop before going to bed. Almost…
Technical Guide Where Finished Logs Go — Deciding Between Delete, Keep, and Compress
The incident investigation is over. The postmortem is written. What's left on disk is the tens of gigabytes of…
Technical Guide The Night the Log Wouldn’t Read — Four Character-Encoding Traps and How to Tell Them Apart
[Update, 16 October 2026] Speed today — Shift-JIS, EUC-JP and UTF-16 can now be searched fast through an index…
Technical Guide I Replaced 21,994 Occurrences in a 10GB, 100-Million-Line File in 16.8 Seconds. It Cost 3.7MB
This is what happened when UwView Pro's Edit Upgrade — Huge Files, No Rewriting was pointed at a 100-million-l…
Technical Guide You Found the ERROR. You Still Can’t Find the Cause — Four Ways to Trace Causality in Logs
--> grep ERROR worked. The red line is right there on your screen. And the "root cause" field in your report i…
Technical Guide “This File Is Too Large to Open” — Four Go-To Tools That Sink Under Huge Files, and What Comes Next
[Update, 16 October 2026] Speed today — 50 GB is about the same; even at 3 GB, the gap now opens from the seco…
Technical Guide You Found the ERROR. The Cause Is in the Lines Before It — Tracing Context in a Huge Log
Last time we covered opening a 10GB–50GB log without splitting it and finding "ERROR". But a real incident inv…