system-design – Page 11 – Türker Yıldırım

The database that was 80% dead rows

Deep diveOctober 4, 202210 min read

180 GB on disk and 41 GB of data. A table that was deleted from daily and never shrank.

PHPUnit 9 to Pest, and the migration that was not worth it

Deep diveSeptember 30, 202210 min read

A trial on one suite, honestly reported. Nothing was wrong with the tests we had.

A scheduled task on a second server runs twice

NoteSeptember 25, 20221 min read

The scheduler runs on every host that has a cron entry, which is correct behaviour and is not what anybody wants for a nightly export. Silently doing nothing…

The API version that was never going to be removed

Deep diveSeptember 21, 202215 min read

v1, v2 and v3 in production, and v1 has four clients. Every change is made three times.

OpenTelemetry when the PHP SDK is still beta

Deep diveSeptember 20, 202210 min read

The traces specification is 1.0 and the PHP implementation is not. Three tracing formats and a vendor decision nobody wants to make.

The scale-down that kills a job mid-flight

NoteSeptember 15, 20222 min read

An autoscaler removing a worker sends a termination signal, and a worker that does not handle it loses whatever it was doing. Scaling down is the case nobody…

A read-through cache that stampedes exactly once

Deep diveAugust 24, 202210 min read

A cache entry expired at 09:00 and four hundred requests recomputed it. A latency spike every hour, exactly on the hour.

Bootstrap 5.2, CSS variables, and a theme that stopped being a fork

Deep diveAugust 17, 202210 min read

5.2 in July, and custom properties throughout the components. A Sass fork that had to be rebased on every patch release.

Composer audit, and the advisory that was already fixed

Deep diveAugust 8, 202210 min read

2.4 in August, and an audit command in the tool that already knows. A separate scanner reporting on a lock file it half understood.

CLIENT NO-EVICT, and the connection you must not lose

NoteAugust 5, 20222 min read

When Redis is under memory pressure it evicts client connection buffers, and 7.0 lets a connection opt out of being a candidate. CLIENT NO-TOUCH is the more broadly…