What Happens When You Check an A/B Test Early
Twenty thousand simulated experiments with no real difference in them. Read once at the end, 4.9% came back significant,...
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What Your Monitoring Costs the Database
Metadata queries are expensive because the server assembles the answer by walking itself. Measured on production with th...
How to Find What Is Scanning Your Tables
Knowing a table is scanned tells you little; knowing which statement scans it tells you everything. Reading MySQL's stat...
The Indexes Nobody Reads
Indexes accumulate because nothing ever removes them, and removing one means proving it is unused. MySQL will tell you:...
Your Database Has One Collation for Southeast Asia
MySQL 8 ships 89 collations for utf8mb4 and exactly one is for a Southeast Asian language. Five of them sorted the same...
What a Character Limit Does to Khmer
Truncation looks like the simplest thing a program does, until the same twenty-character limit hands an English reader n...
Your Scheduler Has Never Reported a Failure
Fifty-nine thousand runs, forty-four commands, zero failures — because for background tasks the failure path ran in a pr...
Your Daily Report Is Counting the Wrong Day
A naive date filter and a timezone-aware one disagreed on twelve of twenty-one days, once reporting six items on a day t...
How to Behave When You Are Rate Limited
Five clients, one job, one throttle. Hammering issued 553 requests to fetch 40 things and finished behind the client tha...
A 200 Is Not a Success
With the database stopped the homepage still returned 200, at a fifth of its normal text with none of its articles. Find...
How to Measure Whether Your RAG Is Retrieving the Right Documents
Twenty questions with known answers, run over 205 real documents. Prefixing titles to chunks raised hit@1 from 14 to 17...
What Our Own Site Sends, and Why We Can't Tell You Exactly
We tried to measure our own monthly egress with root on the machine. Three sources gave three answers, and extrapolating...
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