모든 문서
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Publishing a web feed: RSS 2.0, Atom or JSON Feed, and the details readers depend on
Atom requires an id, title and updated per feed and entry with RFC 3339 dates; RSS 2.0 requires channel title, link and description, uses RFC 822 dates and a guid whose isPermaLink defaults to true; JSON Feed 1.1 requires version, title and items with an id and content, served as application/feed+json. Stable IDs, full content, conditional GET and autodiscovery matter more than the format choice.
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Unreal Enhanced Input: compose contexts, modifiers and trigger behaviour
Build input around semantic actions, explicit context ownership and well-defined trigger lifecycles instead of relying on priority alone.
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What connection-pool size relative to CPU cores have teams settled on for a PostgreSQL server, and which measurement made them change it?
Open question: the PostgreSQL wiki offers a sizing formula for active connections built around core count and effective spindle count, and the server's max_connections default is typically 100; what pool sizes have teams actually ended up with after tuning, how far from the formula were they, and what evidence (lock waits, queueing at the pooler, CPU saturation, latency) drove each change?
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Refactoring in kleinen, geprüften Schritten
Refactoring ändert die innere Struktur, nicht das beobachtbare Verhalten. Ein benanntes Refactoring aus dem Katalog nach dem anderen, Tests nach jedem Schritt grün, bei Rot rückgängig statt vorwärts debuggen, Struktur- und Verhaltensänderungen in getrennten Commits – so bleibt die Arbeit sicher und in Minuten prüfbar.
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XML today: well-formed versus valid, namespaces, and when it is still the right choice
A well-formed XML document obeys the syntax; a valid one also satisfies a DTD or schema. Namespaces give every element and attribute an expanded name of namespace URI plus local name, bound through xmlns declarations whose prefixes are arbitrary and whose default form does not apply to attributes. XML remains the right choice for mixed-content documents and for ecosystems whose vocabularies and tooling are already XML.
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Handling Unicode text correctly
Decode bytes to text at the boundary, encode back only on output, normalise when comparing, and remember that a user-perceived character can be several code points; Python's Unicode HOWTO and Unicode TR15 cover the mechanics.
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Reliable and unreliable game messages: choose guarantees by meaning
Separate freshness, ordering and completion requirements, then use sequence numbers and application results without confusing packet delivery with gameplay success.
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Overfitting and regularisation in outline: bias, variance and the penalty knob
A model overfits when it learns noise in the training rows and its validation score falls behind its training score; regularisation trades some fit for stability by penalising large coefficients or limiting model capacity, and learning and validation curves show which side of the trade-off a model is on.
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Checking that nested resource routes bind children to the stated parent
Validate a relationship that coding agents can omit when building nested endpoints: the requested child must belong to the requested parent under the application contract. This is an original fixture design.
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Diagnosing lock waits and deadlocks in PostgreSQL with pg_locks, pg_blocking_pids and lock_timeout
A statement that hangs is usually waiting for a lock held by another transaction: find the waiter in pg_stat_activity (wait_event_type Lock), its blocker with pg_blocking_pids(), and the blocker's state and last statement, then cancel, terminate or wait. log_lock_waits records waits longer than deadlock_timeout, deadlocks are detected and resolved by aborting one transaction, and lock_timeout bounds how long DDL may wait.
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Floating origins: preserve local precision in large game worlds
Separate global location from local simulation coordinates, quantify floating-point spacing, and rebase all dependent spatial state consistently.
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How do teams with tight downtime budgets choose between pg_upgrade in link mode and a logical-replication switchover for major PostgreSQL upgrades?
Open question: the documentation offers pg_upgrade (minutes of downtime, rollback from backup in link or swap mode) and logical replication (seconds of switchover, but no DDL or sequence replication and a full second copy); which have teams chosen at which database sizes and write rates, and what went wrong?
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Unreal Nanite: evaluate virtualised geometry without assuming unlimited detail
Understand what Nanite changes about geometry detail and streaming, then verify material, rendering-path and fallback requirements on representative content.
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Wie sich ein automatisierter Client zu erkennen gibt: User-Agent, Kontaktadresse, robots.txt und Ratenlimits
Was ein Agent, der Seiten abruft oder Schnittstellen aufruft, senden und beachten sollte, damit Betreiber ihn erkennen, seine Halter erreichen und seine Last steuern können: ein User-Agent mit Produkttoken, Version und Beschreibungsseite, die passende robots.txt-Gruppe und der Umgang mit 429 und Retry-After.
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Reading an RFC or standard efficiently
Read the abstract and terminology first, then the normative sections, treating MUST, SHOULD and MAY (RFC 2119) as different obligations; check for updates and errata before relying on details.
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Goroutines, channels and the sync package: Go concurrency in outline
A go statement runs a function call concurrently on a cheap, growable stack; channels move values between goroutines and block until both sides are ready; sync.WaitGroup, Mutex and Once cover the cases where sharing memory is simpler. A data race is a bug whose outcome the memory model only partly constrains, and the -race detector is the tool for finding it.
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Truncating and summarising tool results to fit a context budget
Cap every tool result at a size chosen per tool, filter at the source before returning, keep head and tail with an explicit omission marker and the full output on disk, never cut errors or structured data mid-record, and clear or summarise results once they have been acted on.
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CAP and PACELC as decision aids rather than slogans
CAP forbids only one corner of the design space: perfect availability and linearizable consistency while a network partition lasts. PACELC adds the everyday trade-off between latency and consistency when there is no partition. Used as questions rather than labels, both help decide, per operation, where a system may return stale data and where it must coordinate.
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The PF firewall on FreeBSD: testing pf.conf with pfctl -n before loading it, and a scheduled rollback against SSH lockout
pf.conf rules are organized around a default pass/block policy, optional anchors for attaching sub-rulesets, and are loaded with pfctl -f only after pfctl -nf has parsed them without loading. Because a mistaken rule set can cut off the very SSH session used to apply it, scheduling an unattended revert with at(1) before loading new rules is a common safety pattern (not a PF feature) for testing changes on a remote FreeBSD host.
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make, ping and nc: exit codes that quietly don't check what you'd assume
GNU make's exit code 1 from -q means 'a target needs rebuilding,' not failure; ping's exit code 1 means no reply was received (host down, not a broken ping invocation) while 2 means a real usage/error; and openssl s_client documents that a default connection succeeds (exit 0) even when certificate verification failed, unless -verify_return_error is given.
기계 판독 가능: JSON