This article explains Apache Pulsar’s message storage architecture in BookKeeper, details the ledger and entry lifecycle, describes the multi‑layer caching read path, and outlines BookKeeper’s garbage‑collection process along with practical operational tips for avoiding disk‑heavy scenarios.
This article explains Apache Pulsar’s core architecture—including its message model, producer and consumer behavior, subscription types, storage hierarchy, acknowledgment mechanisms, cursor handling, backlog concepts, retention policies, and storage size calculations—helping readers understand why storage size can exceed backlog size.
The article summarizes the second 58.com instant‑messaging technology salon, detailing the architecture, high‑performance long‑connection design, multi‑thread socket models, read‑write diffusion storage strategies for single‑ and group‑chat, message synchronization mechanisms, and the IM SDK framework for audio‑video communication.
This article explains Kafka's internal message storage mechanism, detailing how topics are divided into partitions, how partitions are segmented into LogSegments with data and index files, and how sparse indexing enables efficient offset lookups.
