linux – Page 9 – Türker Yıldırım

innodb_buffer_pool_size is the only setting that matters first

NoteJune 11, 20212 min read

Almost every MySQL tuning question is answered by whether the working set fits in the buffer pool, and almost every tuning guide starts somewhere else. A hit rate…

maxmemory-policy, and the cache that was a database

NoteJune 7, 20212 min read

The default policy is noeviction, which means a full Redis returns errors on writes rather than evicting anything. noeviction is the right default for an instance holding queue…

Terraform 1.0 is a promise about the next five years

Deep diveJune 2, 202110 min read

A version number that is a compatibility statement rather than a feature list. Three environments described by hand, and the import that is most of the work.

Compose v2 is a plugin, and the hyphen finally goes

Deep diveMay 19, 20219 min read

The same command, spelled two ways, on eight machines. A Python program became a Go plugin, and the container names changed underneath every script.

systemd Restart=on-failure and the loop it creates

NoteMay 17, 20212 min read

A unit that restarts on failure and fails immediately will restart as fast as systemd allows, until the rate limit stops it — and the rate limit is…

A systemd timer instead of cron, for the logs alone

NoteMay 11, 20212 min read

A cron job that fails writes to whatever mail was configured in 2014, and a timer’s output is in the journal alongside everything else. Persistent=true runs a missed…

A Go binary as a sidecar, for the one thing PHP is bad at

NoteApril 21, 20212 min read

A long-lived process holding thousands of connections is not what PHP is for, and a small binary beside it is a smaller change than a rewrite. Keeping the…

The staging environment that was lying

Deep diveApril 8, 202110 min read

It passed on staging four times and failed in production four times. The same code, a different outcome, and five differences nobody had enumerated.

logrotate copytruncate loses lines and nobody says so

NoteMarch 9, 20212 min read

copytruncate copies the file and then truncates the original, and anything written between those two operations is gone. The window is small and the loss is real, and…

Log lines that a machine can read

Deep diveMarch 4, 202110 min read

A grep that needed three regular expressions and a sort. A log line written for a person to read at leisure is not a record you can query.