DongHyeonkaandClaude Opus 5
b2963105a8
The keycloak project ended with four open questions that design could not
settle. A two-VM lab was built to answer them by measurement, and this is
that material: 26 experiments, 125 raw command outputs, 22 browser captures.
Follows the import procedure in README.md.
source/ the originating repository verbatim — 78 documents, 28 SVGs,
8 manifests, plus .source-revision recording the commit
final/ the SSOT
document.md 729 lines written from the 29 experiment documents, not
concatenated: what was predicted, what was measured, and
where the measurement itself was wrong
evidence/raw 125 outputs, flattened to <experiment>__<file> because
the originals collided (01-baseline.txt appeared three
times) and the audit only globs the top level
evidence/meta one per raw file; command and exitCode are null and the
README says why rather than inventing them
evidence/browser 22 captures
assets/ three diagrams through techviz
.techviz/ their VizSpecs
A separate project rather than an addition to keycloak: the B-layer answers
that project's four questions, but the A, C and D layers are about cluster
failure, SSO and operations, and one document.md should hold one subject.
The four question records there can point here through 관계.
Recorded rather than papered over: only three of the 28 diagrams were
remade. The repository forbids hand-drawn SVG and forbids titles inside the
canvas; all 28 originals carry both, so converting them is redrawing, not
reformatting. They stay in source/ and the gap is written into the document.
verify-pipeline.py passes. audit-records.py reports no issues.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
54 lines
2.4 KiB
Markdown
54 lines
2.4 KiB
Markdown
---
|
|
kind: CONCEPT
|
|
slug: messaging-outbox-jdbc-postgresql-c05
|
|
title: 동시성 제어가 전부 데이터베이스에 있다
|
|
topic: state-machines-and-ownership
|
|
project: clean-architecture-backend-template
|
|
status: 게시 전
|
|
sourceRevision: 21234e38cdb9a926cbc92bb97a2aee2e4a7d2916
|
|
rootTreeNode: concept:messaging-outbox-jdbc-postgresql-c05
|
|
evidenceCapturedOn: 2026-09-01
|
|
assets:
|
|
- key: messaging-outbox-jdbc-postgresql-c05
|
|
file: ../../../final/evidence/rendered/messaging-outbox-jdbc-postgresql-c05.svg
|
|
- key: messaging-outbox-jdbc-postgresql-c05-diagram
|
|
file: ../../../final/assets/diagrams/messaging-outbox-jdbc-postgresql-c05.svg
|
|
evidence:
|
|
- ../../../final/evidence/raw/messaging-outbox-jdbc-postgresql-c05.txt
|
|
source:
|
|
- 원본 분석 절은 analysis/messaging/messaging-outbox-jdbc-postgresql.md#L486 이다.
|
|
module: messaging-outbox-jdbc-postgresql
|
|
---
|
|
|
|
# 동시성 제어가 전부 데이터베이스에 있다
|
|
|
|
두 가지 커넥션 획득 방식이 공존하고, Java 쪽에는 락이 없다.
|
|
|
|
## 본문
|
|
|
|
<!-- body:start -->
|
|
|
|
**두 가지 커넥션 획득 방식이 공존한다.**
|
|
|
|
## 커넥션을 얻는 두 방식
|
|
|
|
:::evidence key="messaging-outbox-jdbc-postgresql-c05-diagram" alt="커넥션 획득에서 릴레이와 저널 두 상자로 화살표가 나가고 화살표에 독립 커넥션과 호출자 트랜잭션이 붙은 구조" caption="커넥션을 얻는 두 방식" zoom="false"
|
|
:::
|
|
|
|
릴레이 연산이 비즈니스 트랜잭션에 합류하면 안 되므로 `withConnection` 의 선택은 타당하다. 다만 그 판단이 주석으로 남아 있지 않고, 같은 리프의 저널은 반대 방식을 쓴다. §17 P3.
|
|
|
|
## OutboxRelayWorker 참조 위치
|
|
|
|
:::evidence key="messaging-outbox-jdbc-postgresql-c05" alt="코드베이스에서 OutboxRelayWorker 를 검색한 출력 17줄. 이 기록이 세는 참조가 그 출력에 그대로 보인다." caption="OutboxRelayWorker 코드베이스 검색 — 17줄 · exit 0" zoom="true"
|
|
:::
|
|
|
|
## 동시성 원시 요소가 전부 DB에 있다
|
|
|
|
`FOR UPDATE SKIP LOCKED`(청구), 서버측 토큰 증가, 펜싱 술어, `ON CONFLICT DO NOTHING`, 복합 기본키. Java 쪽에 락이 없다.
|
|
|
|
## 수명주기
|
|
|
|
`OutboxRelayWorker` 는 데몬 스레드 1개, `setExecuteExistingDelayedTasksAfterShutdownPolicy(false)`, `start()` 멱등, `stop(deadline)` 드레인 후 실패 시 `shutdownNow()`. 셋 다 근거 주석이 있다(`:79-88`, `:92`, `:121-122`).
|
|
|
|
<!-- body:end -->
|