Original, source-backed articles about running small systems, static sites, HTTP, DNS, TLS, and operations.
Posts are original articles written for this site. Each one is script-free, source-backed, and tied to the same operational reality the rest of the site records: how a small, static, publicly served system is built, secured, and kept honest.
UNLOGGED table contents trade crash recovery for less WAL
An unlogged PostgreSQL table keeps normal SQL transaction behavior while giving up crash recovery for its contents. It is useful for reproducible staging data, but a committed row is not guaranteed to survive a server crash. The distinction is between clean operation and recovery after an unclean shutdown, not between ordinary queries and every restart.
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EXPLAIN plans reveal the route of a query
EXPLAIN shows the execution plan selected for a statement. It helps locate expensive work and mistaken estimates, but a slow request can also involve locks, network transfer, or application behavior outside the plan. Use plan evidence to test a specific hypothesis rather than assuming that every performance problem requires a different scan or another index.
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A bare command the shell cannot find
“Command not found” identifies a lookup failure, but lookup does not always mean walking every directory in PATH. In ordinary Bash, a command word without a slash can resolve to a function, builtin, cached executable path, or a newly searched executable. An alias may already have changed the command while the input was read. Inspect the shell that actually reported the failure before reinstalling a tool that may already exist.
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Choose an nginx balancing method by the decision it actually makes
An upstream group names candidate backend endpoints, and its balancing method chooses among eligible peers. Round robin distributes selections by weight; least connections considers active connections and weights; hash methods use a selected key for affinity. These decisions describe routing policy. They do not automatically measure CPU utilization, guarantee equal response times, or make local session state durable when a peer disappears.
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Query parameters preserve the boundary between values and SQL
A parameterized query sends the database instruction and its values through distinct API arguments. The database interprets the instruction as SQL and uses each parameter where a value belongs. This boundary works in embedded engines such as SQLite as well as client-server databases; it does not depend on a network exchange or on an application explicitly managing named server statements.
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Load shedding protects the system
Load shedding deliberately refuses some work when accepting everything would threaten useful service. The aim is to preserve capacity for work that can still complete, not to promise that every accepted request will be fast or important. Rejection is itself work, so the admission point and its cost matter as much as the threshold.
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GIN indexes speed up full-text and multi-value search
A GIN index stores searchable keys extracted from values and maps those keys to rows. Full-text documents, arrays, and JSONB can all use this access method, but each indexed expression needs an appropriate operator class. GIN is a family of supported searches, not one index that automatically accelerates unrelated columns, data types, or predicates.
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Pushgateway retains batch metrics until their lifecycle is handled
A short-lived job can finish before Prometheus next scrapes it. Pushgateway offers an intermediary that retains pushed metrics for later scraping, but it is not the default answer for every short process. Prometheus recommends it primarily for suitable service-level batch outcomes. The retained data has a lifecycle independent of the job, so successful scraping does not prove the job recently ran or succeeded.
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