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3,240 articles, newest first · page 37 of 54. For subject-based browsing use topics; for keyword lookup try search. Dates shown are assigned archive dates that order the library; they are not historical publication records.

2024
Nov 4, 2024 Timing Constraints: Clock Definitions, Groups, and Exceptions How a constraint file tells the timing engine what the clocks are and which paths matter, and why an over-generous false path is a correctness bug rather than an optimization. hardware engineering · intermediate
Nov 4, 2024 VXLAN Header Layout and the Scope of the VNI A byte-level reading of the eight-byte VXLAN header, why the tenant identifier is twenty-four bits, and what the reserved fields constrain. networking · foundational
Nov 3, 2024 Entropy Sources and the Path from Randomness to a Key Why a generated key is capped by the entropy behind it, how kernel pools and deterministic generators condition that entropy, and where the path breaks. cryptography · foundational
Nov 3, 2024 Keyed State Layout and the Cost of Keeping It What a keyed operator stores per key, how state backends trade heap for disk, and why a growing key space is the failure that has no trigger. data engineering · intermediate
Nov 3, 2024 Value Prediction and the Limits of Speculating on Data What it would take to break true data dependencies, why value prediction attacks a different limit than branch prediction, and the correctness and cost barriers that keep it out of shipping cores. computer architecture · advanced
Nov 2, 2024 CBC-MAC Ends at the Last Block, and That Is the Problem Chaining a block cipher over a message authenticates only the final block, so variable-length messages invite splicing attacks; CMAC adds two derived subkeys to close the hole. cryptography · foundational
Nov 2, 2024 Feedback Effects That Change Service Demand How retries, timeouts, circuit breakers, and admission control alter the load a system receives, and why a positive feedback loop makes a capacity plan invalid at exactly the moment it is needed. performance engineering · advanced
Nov 1, 2024 Causality and Out-of-Thin-Air Values in the Java Model Why the Java Memory Model needed a causality order rather than happens-before alone, and how the happens-before consistency rules leave room for a value with no writer. memory systems · advanced
Nov 1, 2024 Oracles, Relativization, and the Limits of Diagonalization How adding an oracle changes what a proof can see, why there are oracles that collapse P and NP and oracles that separate them, and what that implies for any argument that treats machines as black boxes. computation theory · advanced
Nov 1, 2024 RSA Padding and Why Textbook RSA Fails Textbook RSA is multiplicative and deterministic, which makes it malleable and open to chosen-ciphertext attacks; how OAEP and PSS impose the structure that closes them. cryptography · intermediate
October
Oct 31, 2024 Star Schemas and the Cost of Normalizing a Dimension What denormalizing a dimension into one wide table buys at query time, what it costs in update work, and why snowflaking usually loses on columnar storage. data engineering · foundational
Oct 29, 2024 Change Amplification: How Coupling Sets the Price of an Edit Why a one-line rule change can require edits in seven files, how to tell legitimate breadth from amplification, and which couplings multiply the cost of every future change. software architecture · foundational
Oct 29, 2024 Desired State, Observed State, and the Reconciliation Loop Why declarative provisioning converges instead of executing steps, what a provider must implement to make convergence possible, and where the model stops describing reality. cloud infrastructure · foundational
Oct 29, 2024 Range Coding and rANS as Practical Entropy Coders How byte-oriented range coders and asymmetric numeral systems implement the arithmetic-coding ideal with integer state, and why interleaving makes the rANS variant parallelizable. computation theory · intermediate
Oct 28, 2024 Bytes Fetched per Field: Layout as a Bandwidth Decision Why array-of-structs and struct-of-arrays trade differently against cache line granularity, and how to compute the bytes moved per field actually read. performance engineering · foundational
Oct 28, 2024 Scrape Interval, Lookback Delta, and the Resolution of a Rate How sampling period sets the highest frequency a rate graph can show, why aliasing turns a steady signal into a beat pattern, and what lookback staleness does at the edges. observability · foundational
Oct 28, 2024 Why Depth Interpolates as 1/w and Screen-Space Attributes Do Not Perspective projection destroys linearity in screen space, so barycentric interpolation of depth requires the reciprocal of w, and the same reciprocal distributes every varying correctly. computer graphics · foundational
Oct 27, 2024 Sample Positions, Trilinear Interpolation, and the Half-Cell Offset Why a scalar grid carries two coordinate conventions, what trilinear interpolation costs and how it errs, and how resampling a field to a second grid trades resolution against aliasing. scientific computing · foundational
Oct 26, 2024 Stack Canaries and What They Actually Detect How a random guard word between local buffers and saved control data turns a linear stack overflow into a detectable event, and which overflows it cannot see. memory systems · foundational
Oct 25, 2024 Character Encoding Determination Before the Parser Runs A byte order mark, an HTTP charset parameter, and a meta prescan of the first 1024 bytes compete to decide how bytes become characters, and a late declaration can force a reparse. web platform · advanced
Oct 24, 2024 fork and exec: Which Descriptors Survive and Why Between fork and exec a child inherits every open descriptor, and only a per-entry flag can prevent it. The inheritance rules, the leak they cause, and the atomicity problems that follow from closing descriptors after the fact. systems programming · intermediate
Oct 24, 2024 Recursion Schemes: Catamorphisms, Anamorphisms, and Hylomorphisms The zoo of structured recursion operators, what each adds over the plain fold, and how the composition of a fold with an unfold collapses into a single pass. programming languages · intermediate
Oct 24, 2024 Set Associativity and the Address Bits a Cache Decodes How a physical address splits into tag, index, and offset, why direct-mapped and fully associative arrays are the two ends of one trade, and what conflict misses actually cost. memory systems · foundational
Oct 24, 2024 Systolic Arrays and Dataflow Scheduling How a grid of multiply-accumulate cells reuses operands by moving them between neighbours, why the schedule is the compiler's job, and where the approach stops paying. computer architecture · intermediate
Oct 23, 2024 Nulls, Three-Valued Logic, and the Constraints They Break How UNKNOWN propagates through SQL predicates, why NOT IN behaves unexpectedly with nulls, and which integrity constraints a null silently satisfies. databases · intermediate
Oct 23, 2024 Small-to-Large Merging and the DSU on Tree Technique Why merging the smaller container into the larger bounds total moves to n log n, and how the same accounting answers subtree queries by reusing one mutable structure. data structures · intermediate
Oct 22, 2024 Checkpoint and Restore of a Running Container How a process tree is frozen, serialised to disk and reconstituted, which state can be captured exactly and which state must be re-established cooperatively. virtualization · advanced
Oct 22, 2024 Definedness Tracking: What Valgrind Memcheck Knows That Shadow Bytes Do Not Memcheck runs the program on a synthetic CPU and carries a definedness bit per bit of data, catching reads of uninitialised memory that address-based checks cannot see. systems programming · advanced
Oct 22, 2024 Writing Modes and Logical Properties How writing-mode rotates the inline and block axes, what direction changes about line layout, and why logical properties resolve against a different rectangle than their physical counterparts. web platform · advanced
Oct 20, 2024 Memoization Mechanics: Cache Keys, Laziness, and Recursion Depth How top-down memoization turns a recursion tree into a DAG, what the cache key must contain to be sound, and why the lazy traversal sometimes loses to a full table. algorithms · foundational
Oct 19, 2024 Low-Discrepancy Sequences and the Correlation They Leave Behind How the radical inverse builds a progressive sequence, what discrepancy measures, and why a sampled sequence strands its structure at correlated dimensions. computer graphics · advanced
Oct 18, 2024 Compensating for Multiple Scattering in Rough Specular Models Why a single-scattering microfacet lobe loses energy as roughness rises, and how a tabulated directional albedo plus a complement lobe restores the budget without breaking reciprocity. computer graphics · intermediate
Oct 18, 2024 MAC Address Structure and How a NIC Filters Group Traffic The bit layout of a 48-bit MAC address, why the I/G and U/L bits sit in the first transmitted byte, and the receive-filter modes a NIC applies before any driver code runs. networking · foundational
Oct 18, 2024 Parsing Untrusted Binaries Without Trusting Their Length Fields Why every offset in an executable is an attacker-controlled integer, how a bounded cursor converts that into a single failure path, and which structural checks the formats leave to the reader. systems programming · advanced
Oct 18, 2024 The Fully Connected Layer as an Affine Map What a dense layer computes, why the weight matrix is transposed and the bias broadcast, and how the parameter count, the backward pass cost, and the collapse of stacked layers follow from one identity. deep learning · foundational
Oct 17, 2024 Configure Tests That Execute Cannot Survive a Cross Build Run-time feature checks answer questions about whichever machine runs them, and caching makes the wrong answers outlive the build. Which tests can be converted, and which must be replaced by a declaration. systems programming · intermediate
Oct 16, 2024 Cell-Based Isolation and the Blast Radius of a Bad Deployment How partitioning a regional deployment into independent cells limits the reach of a failure, what the cell map costs, and why cells differ from availability zones. cloud infrastructure · advanced
Oct 16, 2024 Confidence Intervals for the Difference Between Two Benchmark Runtimes Why two overlapping intervals can still hide a real difference, how the standard error of a difference is computed from paired or independent samples, and what a ratio estimate needs before it is trustworthy. performance engineering · intermediate
Oct 16, 2024 Load Balancer Listeners and Target Selection How a listener decides to accept a connection, how a target is chosen from a registered set, and why the balancer terminates the client connection instead of forwarding packets. cloud infrastructure · intermediate
Oct 16, 2024 Network Namespaces and Virtual Ethernet Pairs How a process gets a private set of interfaces, routes and firewall rules, and how a veth pair connects that private stack to the host without either side sharing a socket table. operating systems · intermediate
Oct 16, 2024 The vDSO and System Calls That Never Trap How a read-only code page mapped into every process serves clock and CPU queries without a privilege transition, and what that costs in portability. operating systems · intermediate
Oct 15, 2024 Gaussian Mixture Models and the EM Lower Bound Soft cluster membership follows from a latent-variable model whose log-likelihood has no closed-form maximizer; the EM iteration maximizes a lower bound that is tight at the posterior, and it can also drive components to degenerate solutions. machine learning · intermediate
Oct 15, 2024 Interval Joins Over Event Time Why a stream-stream join must buffer both sides, how the watermark of the slower input gates the match, and where the retained state actually goes. data engineering · intermediate
Oct 15, 2024 Rate and Capacity in the Sponge Construction How SHA-3 absorbs and squeezes through a fixed permutation, why capacity rather than digest width determines the security level, and what the rate costs in throughput. cryptography · foundational
Oct 15, 2024 Reading a Diff for the Mechanism It Changed A bisected revision is a pointer to a change, not a cause. Separating default-value, ordering, and resource-lifecycle differences from cosmetic ones is what turns a pointer into a mechanism. observability · intermediate
Oct 14, 2024 Two-Level Flow Control and Why Credit Must Be Advertised How stream and connection limits interact, why a receiver cannot simply stop reading, and what happens to credit when a stream is reset. internet protocols · intermediate
Oct 13, 2024 Disk Image Integrity and Chain of Custody Mechanics What a hash establishes about a disk image, why acquisition order determines what the image can prove, and how write blockers and hashing after the fact differ in evidentiary value. security · foundational
Oct 12, 2024 LZ77 and LZ78 Parsing: Offsets Versus a Phrase Dictionary How a sliding window turns repetition into (distance, length) pairs, why LZ78 replaces the window with an explicit phrase table, and what each costs at decode time. algorithms · advanced
Oct 10, 2024 Disseminating Suspicion by Gossip: Anti-Entropy, Rumor Mongering, and Merge Order How a suspicion reaches every node without a broadcast tree, why the merge rule must be a total order, and what the log factor in convergence time actually depends on. distributed systems · intermediate
Oct 10, 2024 Grain: What One Row of a Fact Table Means Why the grain declaration precedes every column choice, how it fixes which measures can be summed, and what a join at the wrong level does to a count. data engineering · foundational
Oct 10, 2024 Out-of-Fold Target Encoding for High-Cardinality Categoricals How smoothing trades bias for variance in target encoding, why the encoding must be computed out of fold, and what the left-out fold estimate costs in noise. machine learning · intermediate
Oct 10, 2024 The Interception Surface of a Virtual GPU A GPU presents a register file, a bus-mastering DMA engine, and an interrupt source at once; sharing one means deciding which of the three the host keeps control of. gpu computing · foundational
Oct 9, 2024 HNSW Layer Assignment and the Greedy Descent How a hierarchical proximity graph assigns levels by an exponential draw, why the top layers act as a coarse skip list, and what ef actually bounds during the search. information retrieval · intermediate
Oct 9, 2024 Spectre, Site Isolation, and the Limits of the Origin Boundary Why speculative execution made the origin a weaker boundary than it appears, how process-per-site and response blocking reduce the exposure, and which timing channels remain open. web platform · advanced
Oct 7, 2024 Limiters, the TVD Condition, and Shock Capture Why a second-order scheme oscillates at a discontinuity, how the total variation diminishing condition forbids new extrema, and what a slope limiter must satisfy to preserve both properties. scientific computing · advanced
Oct 7, 2024 Red-Black Colouring as a Height Proxy How one bit per node encodes a 2-3-4 tree, why the colour rules make insertion repair terminate early, and where the two-to-one height constant comes from. data structures · intermediate
Oct 5, 2024 Composite Objectives: Compressing Multi-Signal Health into a Single Score How normalization, weighting, and aggregation order determine what a composite objective means, and why the same weights can hide opposite failure patterns. observability · advanced
Oct 5, 2024 Setup and Hold Time, Metastability, and the Two-Flop Synchronizer Why a flip-flop needs its input stable around the clock edge, how a near-threshold sample resolves probabilistically, and how cascaded flops bound the failure rate. hardware engineering · intermediate
Oct 4, 2024 Cosine and Linear Decay Schedules as Step-Size Integrals What a learning rate schedule controls beyond the final value, how the shape distributes total parameter displacement across training, and why the choice between linear and cosine changes little at equal area. deep learning · intermediate
Oct 4, 2024 Slerp, Squad, and the Cost of Interpolating Rotations Why component-wise quaternion interpolation fails, what slerp computes and what it costs, and how squad and exponential maps extend the same idea to a whole curve. computer graphics · foundational

2024

October