Upbeatden
Long-form technical notes, written by operators for operators.
Practical Notes on Postgres Connection Pooling
September 17, 2026
Handling PostgreSQL backends imposes substantial overhead because each active client spawns a dedicated process consuming significant RAM, making intermediary connection management mandatory at scale. While session-level pooling preserves compatibility seamlessly, transaction pooling aggressively reassigns connections between queries, breaking features like LISTEN channels, advisory locks, and runtime configuration parameters.
Operational headaches with connection proxies usually stem from poor connection hygiene: forgotten checkouts left dangling in application code, cursors maintained across idle sleep loops, and large migrations hogging pooled slots. Enforcing transaction pooling surfaces these bad patterns immediately by terminating unsupported stateful operations.
Reading Latency Percentiles Without Fooling Yourself
July 24, 2026
Averages conceal what percentiles reveal: the request mix's tail. A service averaging fifty milliseconds can still be sending one in twenty users through a two-second odyssey, and those users - the ones hitting the cold paths, the expired sessions, the overloaded shard - are the ones filing the tick…
Cache Invalidation Patterns That Survive Traffic
June 8, 2026
Everyone quotes the two hard things joke; fewer people ship caches engineered against stampede. The pattern that matters most is request collapsing: when a hot key expires, exactly one worker rebuilds while everyone else serves slightly stale data, which turns a cache miss from a database incident i…
Understanding TLS 1.3 Session Resumption
June 17, 2026
TLS 1.3 collapsed the handshake to a single round trip, but the real latency win for repeat visitors comes from resumption. A client presenting a valid pre-shared key can skip straight to encrypted application data, which on mobile networks can be the difference between a page that feels instant and…
Email Deliverability: Authentication Beyond SPF
May 17, 2026
Traditional SPF checking fails to address modern deliverability challenges on its own. While an envelope IP check might succeed, mismatched headers trigger spam filters that prioritize cryptographic DKIM validations and broader DMARC policy rules.…
More reading
- Why Edge Caching Still Matters in 2026 — Infrastructure, June 24, 2026
- Structuring DNS for Reliability — Networking, June 1, 2026
- When to Choose a Queue Over a Request — Engineering, May 27, 2026
About us
We are a small team of infrastructure engineers and technical writers. We publish what we learn running production systems: incident retrospectives, protocol deep-dives and tooling notes.