Hands-on Python json vs orjson vs msgpack lab: encode/decode MB/s on records, nested, and unicode payloads. Real p50 numbers measured on localhost box.
Hands-on SHA-256 vs BLAKE2b vs xxHash hash throughput on 64MiB buffers (SHA-1/SHA3 labeled). Real MB/s with OpenSSL and xxHash versions on the lab box.
Hands-on SQLite WAL vs DELETE vs OFF journal_mode lab: insert/update RPS (FULL/NORMAL sync), plus WAL checkpoint cost. Real p50 numbers on localhost box.
Hands-on zstd vs gzip vs lz4 on 64MiB payloads (real /usr text, mixed, urandom). Measured compress/decompress MB/s and ratio at default levels. No Docker.
Hands-on fsync vs fdatasync vs none: per-write and every-N sync on 256B and 4KiB records. Real p50/p95 show about 100-200x durability tax on localhost
Hands-on nice/ionice lab: victim nice19 under 6 hogs ~5.7× slower (p95 ~7.4s); ionice idle O_DIRECT read ~6.1× under writers. Real numbers, no Docker.
Hands-on TCP_QUICKACK lab: default QA=1 on loopback; WWR set-once ~18 µs; reassert QA=1 under Nagle p95 ~48 ms, OutSegs ~13×. Real numbers, no Docker.
Hands-on ctx-switch lab: process pipe RTT p50 3.2 us (~0.50M sw/s); thread pipe 2.85 us; Event 9.3 us; 6 hogs blow p95 to 19 us. Real numbers, no Docker.
Hands-on asyncio vs ThreadPool lab: sleep 58.7× vs 44×; delayed TCP 13.8× vs serial; fast-echo trap loses; CPU flat. Real localhost numbers, no Docker.
Hands-on flock lab: uncontended LOCK_EX p50 0.33 us; waiter ~50 ms hold; w8 p50 ~36 ms; LOCK_NB 99% fail; LOCK_SH ~6.7x wall. Real numbers, no Docker.
Hands-on stdout buffering lab: full buffering maximizes throughput, while line and unbuffered modes restore live visibility on pipes.
Hands-on ProcessPool vs ThreadPool lab: pure-Python threads lose to processes, hashlib threads help, and sleep I/O favors threads.