Kevin Tung·9h agoThe ID Was 9007199254740993. The Client Looked Up 9007199254740992.JSON kept the digits of 9007199254740993. Node JSON.parse of that number field produced 9007199254740992 and hit the neighbor row.
Kevin Tung·1d agoThe 30th open() Failed With EMFILE. Closing Each File Completed 1,000.At a soft limit of 32 with 3 inherited FDs, the 30th open() failed with EMFILE. Closing each file completed 1,000 opens.
Kevin Tung·2d agoThe Program Printed 200 Lines. The Pipe Showed None Until It Exited.Piped default Python showed 0 of 200 lines mid-run. flush=True, python -u, and PYTHONUNBUFFERED=1 without -I showed all 200.
Kevin Tung·3d agoEight Teams, Each On Time 80% of the Time. The Change Ships On Time 17% of the Time.In a hypothetical 100,000-trial model, eight independent 80% teams are on time 16.8% of the time (0.80 to the eighth, 17% in the title).A response icon1A response icon1
Kevin Tung·4d agoThe Backup Job Was Green. The Backup Was Incomplete.Without pipefail, a producer that exited 2 still left a green job: gzip exited 0, gzip -t passed, and restore found 20 of 50 rows.
Kevin Tung·5d agostrace Counted 19,200 Missing-File Calls Under the Search Path. The Catalog Path Made None.The start was slow and the CPU was boredA response icon1A response icon1
Kevin Tung·6d agoCalling fsync on Every Write Measured 8.7k Writes/s. Sharing One fsync Across 128 Writes Hit 219k.Per-write sync median 8.7k wps with 512 fsyncs; batch-128 median 219k wps with 4 fsyncs, while p50 rose from 93µs to ~382µs.
Kevin Tung·Nov 8Deleting a Log File Does Not Close ItUnlink removes a name, not an open reference. A local Linux demo shows why rotation needs acknowledgement from readers as well as writers.
Kevin Tung·Nov 7Before You Run Another Experiment, Name the Decision It Could Change.Buy evidence that can change an executable choice, then give the decision an owner, a reversal bound, and a stop rule.
Kevin Tung·Nov 6Walking History Took 744 Test Runs to Find the Regression. git bisect run Needed 13.On a seeded 1000-commit history, a linear walk burned 744 oracle invocations. git bisect run needed 13 — including two exit-125 skips — and…
