# defrag

Published articles for defrag.

This is one page of public article previews, not the complete archive. Follow Next page to continue. Summaries are not the original full articles.

## 【etcd】写入路径深读：Txn、mod revision 与 quota/alarm

DevFeed: [【etcd】写入路径深读：Txn、mod revision 与 quota/alarm](<https://devfeed.tech/articles/etcd-txn-mod-revision-quota-alarm-33989.md>)

Original publisher: [Read original article](<https://quant67.com/post/etcd/07-write-path/07-write-path.html>)

Author: Liao Tonglang

Published: 2026-08-26T00:00:00Z

Content type: tutorial

Language: zh

Sources: [土法炼钢 - 系统与基础设施](<https://devfeed.tech/sources/source-4.md>)

Topics: [etcd](<https://devfeed.tech/topics/etcd.md>), [Back end](<https://devfeed.tech/topics/backend.md>), [Raft](<https://devfeed.tech/topics/raft.md>), [Remote Procedure Call (RPC)](<https://devfeed.tech/topics/rpc.md>), [maintenance](<https://devfeed.tech/topics/maintenance.md>)

Tags: [alarm](<https://devfeed.tech/tags/alarm.md>), [apiserver](<https://devfeed.tech/tags/apiserver.md>), [applied-index](<https://devfeed.tech/tags/applied-index.md>), [apply](<https://devfeed.tech/tags/apply.md>), [batch](<https://devfeed.tech/tags/batch.md>), [bbolt](<https://devfeed.tech/tags/bbolt.md>), [committed-index](<https://devfeed.tech/tags/committed-index.md>), [compaction](<https://devfeed.tech/tags/compaction.md>), [defrag](<https://devfeed.tech/tags/defrag.md>), [distributed](<https://devfeed.tech/tags/distributed.md>), [errcompacted](<https://devfeed.tech/tags/errcompacted.md>), [etcd](<https://devfeed.tech/tags/etcd.md>), [follower](<https://devfeed.tech/tags/follower.md>), [k8s](<https://devfeed.tech/tags/k8s.md>), [kubernetes](<https://devfeed.tech/tags/kubernetes.md>), [mod-revision](<https://devfeed.tech/tags/mod-revision.md>), [nospace](<https://devfeed.tech/tags/nospace.md>), [quota](<https://devfeed.tech/tags/quota.md>), [revision](<https://devfeed.tech/tags/revision.md>), [txn](<https://devfeed.tech/tags/txn.md>), [v3-5](<https://devfeed.tech/tags/v3-5.md>), [v3-5-33](<https://devfeed.tech/tags/v3-5-33.md>)

### AI overview

This tutorial explains the etcd v3.5.33 write path from gRPC requests through Raft proposal, quota checks, MVCC apply, and ModRevision assignment. It also describes proposal backpressure, backend quota accounting, and how a NOSPACE alarm blocks writes while reads, deletes, and maintenance operations can continue.

### Source excerpt

走读 etcd v3.5.33 写入路径：raftRequest 背压、Txn compare/mod 与 ModRevision 分配、backend quota 与 NOSPACE alarm 如何把集群推入只读。

## 【etcd】Compaction、Defrag 与容量：quota、alarm 与 SLO

DevFeed: [【etcd】Compaction、Defrag 与容量：quota、alarm 与 SLO](<https://devfeed.tech/articles/etcd-compaction-defrag-quota-alarm-slo-33994.md>)

Original publisher: [Read original article](<https://quant67.com/post/etcd/12-compaction-quota/12-compaction-quota.html>)

Author: Liao Tonglang

Published: 2026-08-26T00:00:00Z

Content type: tutorial

Language: zh

Sources: [土法炼钢 - 系统与基础设施](<https://devfeed.tech/sources/source-4.md>)

Topics: [etcd](<https://devfeed.tech/topics/etcd.md>), [Raft](<https://devfeed.tech/topics/raft.md>), [Kubernetes](<https://devfeed.tech/topics/kubernetes.md>)

Tags: [alarm](<https://devfeed.tech/tags/alarm.md>), [bbolt](<https://devfeed.tech/tags/bbolt.md>), [benchmark](<https://devfeed.tech/tags/benchmark.md>), [compaction](<https://devfeed.tech/tags/compaction.md>), [defrag](<https://devfeed.tech/tags/defrag.md>), [distributed](<https://devfeed.tech/tags/distributed.md>), [errcompacted](<https://devfeed.tech/tags/errcompacted.md>), [etcd](<https://devfeed.tech/tags/etcd.md>), [follower](<https://devfeed.tech/tags/follower.md>), [kubernetes](<https://devfeed.tech/tags/kubernetes.md>), [lag](<https://devfeed.tech/tags/lag.md>), [leader](<https://devfeed.tech/tags/leader.md>), [mvcc](<https://devfeed.tech/tags/mvcc.md>), [nospace](<https://devfeed.tech/tags/nospace.md>), [performance](<https://devfeed.tech/tags/performance.md>), [quota](<https://devfeed.tech/tags/quota.md>), [raft](<https://devfeed.tech/tags/raft.md>), [resourceversion](<https://devfeed.tech/tags/resourceversion.md>), [v3](<https://devfeed.tech/tags/v3.md>), [v3-5](<https://devfeed.tech/tags/v3-5.md>), [v3-5-33](<https://devfeed.tech/tags/v3-5-33.md>), [watch](<https://devfeed.tech/tags/watch.md>)

### AI overview

This technical article explains how etcd v3.5.33 compaction, defragmentation, quota handling, and the NOSPACE alarm interact. It distinguishes revision-history removal from bbolt file reclamation, describes periodic and revision-based auto-compaction, and connects retention, quota, defrag pauses, and Watch or Kubernetes control-plane behavior to operational SLOs.

### Source excerpt

钉 etcd v3.5.33 MVCC compaction 与 bbolt defrag 的分工、auto-compaction 保留窗口、quota-backend-bytes 与 NOSPACE alarm 写入门，以及 ErrCompacted 如何写进 Watch SLO。