perf(filemeta): phase-1~3 rename_data metadata optimization (#3011)

* chore(perf): harden amd64 profiling benchmark flow * fix(profiling): isolate bench buckets and map protobuf conflict * perf: avoid blocking owned local writes * style: format profile admin handler * docs: clarify observability trace validation * perf: reduce mkdir overhead on local writes * perf: add rename_data meta microbenchmark * perf(filemeta): fast-path data_dir decode in version meta * perf(filemeta): collapse data-dir lookup into one scan * perf(filemeta): reduce scan allocs and refresh meta bench * perf(ecstore): skip mkdir path on read-only open * perf(filemeta): single-pass unshared data-dir scan * perf(filemeta): add two-key inline remove fast path * perf(filemeta): compare remove-two keys by bytes first * bench(ecstore): add remove_two-only micro benchmark * bench(ecstore): stabilize rename_data meta benchmark timing * bench(ecstore): align rename_data path with remove_two * perf(filemeta): avoid uuid string alloc in remove_two * perf(filemeta): add fast-path for empty inline data * perf(filemeta): streamline add_version match branch * perf(filemeta): fast-return remove_key on miss * perf(filemeta): speed up add_version insertion lookup * style(ecstore): normalize formatting in perf-tuning files * refactor(filemeta): unify inline data removal paths
2026-08-11 23:56:53 +00:00 · 2026-05-19 18:20:24 +08:00
parent f695870626
commit 25c6bdf490
16 changed files with 1059 additions and 177 deletions
@@ -54,6 +54,46 @@ Strict mode is available when you explicitly want `/health/ready == 200` as the
 WAIT_PROBE_MODE=ready ./scripts/run_four_node_cluster_failover_bench.sh
 ```

+### Profiling + Trace Validation
+
+The profiling-focused 4-node compose keeps profiling enabled and points RustFS
+to an OTLP/HTTP collector endpoint:
+
+```bash
+docker compose -f .docker/compose/docker-compose.cluster.local-build.profiling-amd64.yml up -d
+```
+
+Important behavior notes:
+
+- `RUSTFS_OBS_ENDPOINT` is the OTLP/HTTP base URL. RustFS automatically sends
+  traces to `/v1/traces`, metrics to `/v1/metrics`, and logs to `/v1/logs`.
+- Startup usually produces logs and metrics first. That does not guarantee
+  visible traces yet.
+- Trace data becomes obvious only after real HTTP/S3/gRPC requests hit RustFS.
+- `RUSTFS_OBS_LOGGER_LEVEL=info` keeps the top-level request span but filters
+  many nested `debug` spans. If Tempo/Jaeger looks sparse, retry with
+  `RUSTFS_OBS_LOGGER_LEVEL=debug` before suspecting the collector.
+
+Minimal trace verification flow:
+
+```bash
+# 1. Start the profiling compose with richer span visibility.
+RUSTFS_OBS_LOGGER_LEVEL=debug \
+docker compose -f .docker/compose/docker-compose.cluster.local-build.profiling-amd64.yml up -d
+
+# 2. Generate real request traffic after startup.
+curl -I http://127.0.0.1:9000/health
+curl -I http://127.0.0.1:9000/health/ready
+
+# 3. Then inspect Tempo or Jaeger.
+# Grafana: http://localhost:3000
+# Jaeger:  http://localhost:16686
+```
+
+If logs and metrics are present but traces are sparse, the most common cause is
+"no real request traffic yet" or "`info` level filtered nested spans", not an
+OTLP routing failure.
+
 ### (Deprecated) Minimal Observability

 ```bash
@@ -0,0 +1,236 @@
+# Copyright 2024 RustFS Team
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Profiling-first 4-node local-build compose.
+#
+# Goals:
+# - force linux/amd64 runtime/build on Apple Silicon hosts;
+# - enable RustFS built-in CPU profiling;
+# - keep all tuning knobs host-overridable via env.
+#
+# Observability notes:
+# - `RUSTFS_OBS_ENDPOINT` is the OTLP/HTTP base URL. RustFS appends
+#   `/v1/traces`, `/v1/metrics`, and `/v1/logs` automatically.
+# - Logs and metrics usually appear during startup. Traces mainly appear after
+#   real HTTP/S3/gRPC requests create spans.
+# - `RUSTFS_OBS_LOGGER_LEVEL=info` keeps the top-level request trace span but
+#   filters many `debug`-level nested spans. Use `debug` when validating trace
+#   richness rather than collector reachability.
+
+services:
+  node1:
+    platform: ${RUSTFS_DOCKER_PLATFORM:-linux/amd64}
+    image: ${RUSTFS_IMAGE:-rustfs/rustfs:local-4node}
+    build:
+      context: ../..
+      dockerfile: Dockerfile.source
+    hostname: node1
+    environment:
+      - RUSTFS_VOLUMES=http://node{1...4}:9000/data/rustfs{0...3}
+      - RUSTFS_ADDRESS=:9000
+      - RUSTFS_CONSOLE_ENABLE=true
+      - RUSTFS_ACCESS_KEY=${RUSTFS_ACCESS_KEY:-rustfs-cluster-admin}
+      - RUSTFS_SECRET_KEY=${RUSTFS_SECRET_KEY:-rustfs-cluster-secret}
+      - RUSTFS_OBS_ENDPOINT=${RUSTFS_OBS_ENDPOINT:-http://host.docker.internal:4318}
+      # `info` is enough for startup logs/metrics. Use `debug` if Tempo/Jaeger
+      # should show richer nested spans during request-path verification.
+      - RUSTFS_OBS_LOGGER_LEVEL=${RUSTFS_OBS_LOGGER_LEVEL:-info}
+      - RUSTFS_OBS_PROFILING_ENDPOINT=${RUSTFS_OBS_PROFILING_ENDPOINT:-http://host.docker.internal:4040}
+      - RUSTFS_OBS_PROFILING_EXPORT_ENABLED=${RUSTFS_OBS_PROFILING_EXPORT_ENABLED:-true}
+      - RUSTFS_UNSAFE_BYPASS_DISK_CHECK=${RUSTFS_UNSAFE_BYPASS_DISK_CHECK:-true}
+      - RUSTFS_ENABLE_PROFILING=${RUSTFS_ENABLE_PROFILING:-true}
+      - RUSTFS_PROF_CPU_MODE=${RUSTFS_PROF_CPU_MODE:-continuous}
+      - RUSTFS_PROF_CPU_FREQ=${RUSTFS_PROF_CPU_FREQ:-99}
+      - RUSTFS_PROF_OUTPUT_DIR=${RUSTFS_PROF_OUTPUT_DIR:-/tmp/rustfs-profiles}
+      - RUSTFS_OBJECT_MAX_CONCURRENT_DISK_READS=${RUSTFS_OBJECT_MAX_CONCURRENT_DISK_READS:-48}
+      - RUSTFS_OBJECT_IO_BUFFER_SIZE=${RUSTFS_OBJECT_IO_BUFFER_SIZE:-262144}
+      - RUSTFS_OBJECT_MEDIUM_CONCURRENCY_THRESHOLD=${RUSTFS_OBJECT_MEDIUM_CONCURRENCY_THRESHOLD:-6}
+      - RUSTFS_OBJECT_HIGH_CONCURRENCY_THRESHOLD=${RUSTFS_OBJECT_HIGH_CONCURRENCY_THRESHOLD:-12}
+      - RUSTFS_OBJECT_IO_RANDOM_READAHEAD_DISABLE_CONCURRENCY=${RUSTFS_OBJECT_IO_RANDOM_READAHEAD_DISABLE_CONCURRENCY:-8}
+      - RUSTFS_OBJECT_DUPLEX_BUFFER_SIZE=${RUSTFS_OBJECT_DUPLEX_BUFFER_SIZE:-8388608}
+      - RUSTFS_ERASURE_ENCODE_MAX_INFLIGHT_BYTES=${RUSTFS_ERASURE_ENCODE_MAX_INFLIGHT_BYTES:-25165824}
+      - RUSTFS_RUNTIME_WORKER_THREADS=${RUSTFS_RUNTIME_WORKER_THREADS:-12}
+      - RUSTFS_RUNTIME_MAX_BLOCKING_THREADS=${RUSTFS_RUNTIME_MAX_BLOCKING_THREADS:-512}
+      - RUSTFS_ALLOCATOR_RECLAIM_ENABLED=${RUSTFS_ALLOCATOR_RECLAIM_ENABLED:-false}
+    extra_hosts:
+      - "host.docker.internal:host-gateway"
+    volumes:
+      - node1_data_0:/data/rustfs0
+      - node1_data_1:/data/rustfs1
+      - node1_data_2:/data/rustfs2
+      - node1_data_3:/data/rustfs3
+    ports:
+      - "9000:9000"
+    networks:
+      - rustfs-cluster-net
+
+  node2:
+    platform: ${RUSTFS_DOCKER_PLATFORM:-linux/amd64}
+    image: ${RUSTFS_IMAGE:-rustfs/rustfs:local-4node}
+    build:
+      context: ../..
+      dockerfile: Dockerfile.source
+    hostname: node2
+    environment:
+      - RUSTFS_VOLUMES=http://node{1...4}:9000/data/rustfs{0...3}
+      - RUSTFS_ADDRESS=:9000
+      - RUSTFS_CONSOLE_ENABLE=true
+      - RUSTFS_ACCESS_KEY=${RUSTFS_ACCESS_KEY:-rustfs-cluster-admin}
+      - RUSTFS_SECRET_KEY=${RUSTFS_SECRET_KEY:-rustfs-cluster-secret}
+      - RUSTFS_OBS_ENDPOINT=${RUSTFS_OBS_ENDPOINT:-http://host.docker.internal:4318}
+      # `info` is enough for startup logs/metrics. Use `debug` if Tempo/Jaeger
+      # should show richer nested spans during request-path verification.
+      - RUSTFS_OBS_LOGGER_LEVEL=${RUSTFS_OBS_LOGGER_LEVEL:-info}
+      - RUSTFS_OBS_PROFILING_ENDPOINT=${RUSTFS_OBS_PROFILING_ENDPOINT:-http://host.docker.internal:4040}
+      - RUSTFS_OBS_PROFILING_EXPORT_ENABLED=${RUSTFS_OBS_PROFILING_EXPORT_ENABLED:-true}
+      - RUSTFS_UNSAFE_BYPASS_DISK_CHECK=${RUSTFS_UNSAFE_BYPASS_DISK_CHECK:-true}
+      - RUSTFS_ENABLE_PROFILING=${RUSTFS_ENABLE_PROFILING:-true}
+      - RUSTFS_PROF_CPU_MODE=${RUSTFS_PROF_CPU_MODE:-continuous}
+      - RUSTFS_PROF_CPU_FREQ=${RUSTFS_PROF_CPU_FREQ:-99}
+      - RUSTFS_PROF_OUTPUT_DIR=${RUSTFS_PROF_OUTPUT_DIR:-/tmp/rustfs-profiles}
+      - RUSTFS_OBJECT_MAX_CONCURRENT_DISK_READS=${RUSTFS_OBJECT_MAX_CONCURRENT_DISK_READS:-48}
+      - RUSTFS_OBJECT_IO_BUFFER_SIZE=${RUSTFS_OBJECT_IO_BUFFER_SIZE:-262144}
+      - RUSTFS_OBJECT_MEDIUM_CONCURRENCY_THRESHOLD=${RUSTFS_OBJECT_MEDIUM_CONCURRENCY_THRESHOLD:-6}
+      - RUSTFS_OBJECT_HIGH_CONCURRENCY_THRESHOLD=${RUSTFS_OBJECT_HIGH_CONCURRENCY_THRESHOLD:-12}
+      - RUSTFS_OBJECT_IO_RANDOM_READAHEAD_DISABLE_CONCURRENCY=${RUSTFS_OBJECT_IO_RANDOM_READAHEAD_DISABLE_CONCURRENCY:-8}
+      - RUSTFS_OBJECT_DUPLEX_BUFFER_SIZE=${RUSTFS_OBJECT_DUPLEX_BUFFER_SIZE:-8388608}
+      - RUSTFS_ERASURE_ENCODE_MAX_INFLIGHT_BYTES=${RUSTFS_ERASURE_ENCODE_MAX_INFLIGHT_BYTES:-25165824}
+      - RUSTFS_RUNTIME_WORKER_THREADS=${RUSTFS_RUNTIME_WORKER_THREADS:-12}
+      - RUSTFS_RUNTIME_MAX_BLOCKING_THREADS=${RUSTFS_RUNTIME_MAX_BLOCKING_THREADS:-512}
+      - RUSTFS_ALLOCATOR_RECLAIM_ENABLED=${RUSTFS_ALLOCATOR_RECLAIM_ENABLED:-false}
+    extra_hosts:
+      - "host.docker.internal:host-gateway"
+    volumes:
+      - node2_data_0:/data/rustfs0
+      - node2_data_1:/data/rustfs1
+      - node2_data_2:/data/rustfs2
+      - node2_data_3:/data/rustfs3
+    ports:
+      - "9001:9000"
+    networks:
+      - rustfs-cluster-net
+
+  node3:
+    platform: ${RUSTFS_DOCKER_PLATFORM:-linux/amd64}
+    image: ${RUSTFS_IMAGE:-rustfs/rustfs:local-4node}
+    build:
+      context: ../..
+      dockerfile: Dockerfile.source
+    hostname: node3
+    environment:
+      - RUSTFS_VOLUMES=http://node{1...4}:9000/data/rustfs{0...3}
+      - RUSTFS_ADDRESS=:9000
+      - RUSTFS_CONSOLE_ENABLE=true
+      - RUSTFS_ACCESS_KEY=${RUSTFS_ACCESS_KEY:-rustfs-cluster-admin}
+      - RUSTFS_SECRET_KEY=${RUSTFS_SECRET_KEY:-rustfs-cluster-secret}
+      - RUSTFS_OBS_ENDPOINT=${RUSTFS_OBS_ENDPOINT:-http://host.docker.internal:4318}
+      # `info` is enough for startup logs/metrics. Use `debug` if Tempo/Jaeger
+      # should show richer nested spans during request-path verification.
+      - RUSTFS_OBS_LOGGER_LEVEL=${RUSTFS_OBS_LOGGER_LEVEL:-info}
+      - RUSTFS_OBS_PROFILING_ENDPOINT=${RUSTFS_OBS_PROFILING_ENDPOINT:-http://host.docker.internal:4040}
+      - RUSTFS_OBS_PROFILING_EXPORT_ENABLED=${RUSTFS_OBS_PROFILING_EXPORT_ENABLED:-true}
+      - RUSTFS_UNSAFE_BYPASS_DISK_CHECK=${RUSTFS_UNSAFE_BYPASS_DISK_CHECK:-true}
+      - RUSTFS_ENABLE_PROFILING=${RUSTFS_ENABLE_PROFILING:-true}
+      - RUSTFS_PROF_CPU_MODE=${RUSTFS_PROF_CPU_MODE:-continuous}
+      - RUSTFS_PROF_CPU_FREQ=${RUSTFS_PROF_CPU_FREQ:-99}
+      - RUSTFS_PROF_OUTPUT_DIR=${RUSTFS_PROF_OUTPUT_DIR:-/tmp/rustfs-profiles}
+      - RUSTFS_OBJECT_MAX_CONCURRENT_DISK_READS=${RUSTFS_OBJECT_MAX_CONCURRENT_DISK_READS:-48}
+      - RUSTFS_OBJECT_IO_BUFFER_SIZE=${RUSTFS_OBJECT_IO_BUFFER_SIZE:-262144}
+      - RUSTFS_OBJECT_MEDIUM_CONCURRENCY_THRESHOLD=${RUSTFS_OBJECT_MEDIUM_CONCURRENCY_THRESHOLD:-6}
+      - RUSTFS_OBJECT_HIGH_CONCURRENCY_THRESHOLD=${RUSTFS_OBJECT_HIGH_CONCURRENCY_THRESHOLD:-12}
+      - RUSTFS_OBJECT_IO_RANDOM_READAHEAD_DISABLE_CONCURRENCY=${RUSTFS_OBJECT_IO_RANDOM_READAHEAD_DISABLE_CONCURRENCY:-8}
+      - RUSTFS_OBJECT_DUPLEX_BUFFER_SIZE=${RUSTFS_OBJECT_DUPLEX_BUFFER_SIZE:-8388608}
+      - RUSTFS_ERASURE_ENCODE_MAX_INFLIGHT_BYTES=${RUSTFS_ERASURE_ENCODE_MAX_INFLIGHT_BYTES:-25165824}
+      - RUSTFS_RUNTIME_WORKER_THREADS=${RUSTFS_RUNTIME_WORKER_THREADS:-12}
+      - RUSTFS_RUNTIME_MAX_BLOCKING_THREADS=${RUSTFS_RUNTIME_MAX_BLOCKING_THREADS:-512}
+      - RUSTFS_ALLOCATOR_RECLAIM_ENABLED=${RUSTFS_ALLOCATOR_RECLAIM_ENABLED:-false}
+    extra_hosts:
+      - "host.docker.internal:host-gateway"
+    volumes:
+      - node3_data_0:/data/rustfs0
+      - node3_data_1:/data/rustfs1
+      - node3_data_2:/data/rustfs2
+      - node3_data_3:/data/rustfs3
+    ports:
+      - "9002:9000"
+    networks:
+      - rustfs-cluster-net
+
+  node4:
+    platform: ${RUSTFS_DOCKER_PLATFORM:-linux/amd64}
+    image: ${RUSTFS_IMAGE:-rustfs/rustfs:local-4node}
+    build:
+      context: ../..
+      dockerfile: Dockerfile.source
+    hostname: node4
+    environment:
+      - RUSTFS_VOLUMES=http://node{1...4}:9000/data/rustfs{0...3}
+      - RUSTFS_ADDRESS=:9000
+      - RUSTFS_CONSOLE_ENABLE=true
+      - RUSTFS_ACCESS_KEY=${RUSTFS_ACCESS_KEY:-rustfs-cluster-admin}
+      - RUSTFS_SECRET_KEY=${RUSTFS_SECRET_KEY:-rustfs-cluster-secret}
+      - RUSTFS_OBS_ENDPOINT=${RUSTFS_OBS_ENDPOINT:-http://host.docker.internal:4318}
+      # `info` is enough for startup logs/metrics. Use `debug` if Tempo/Jaeger
+      # should show richer nested spans during request-path verification.
+      - RUSTFS_OBS_LOGGER_LEVEL=${RUSTFS_OBS_LOGGER_LEVEL:-info}
+      - RUSTFS_OBS_PROFILING_ENDPOINT=${RUSTFS_OBS_PROFILING_ENDPOINT:-http://host.docker.internal:4040}
+      - RUSTFS_OBS_PROFILING_EXPORT_ENABLED=${RUSTFS_OBS_PROFILING_EXPORT_ENABLED:-true}
+      - RUSTFS_UNSAFE_BYPASS_DISK_CHECK=${RUSTFS_UNSAFE_BYPASS_DISK_CHECK:-true}
+      - RUSTFS_ENABLE_PROFILING=${RUSTFS_ENABLE_PROFILING:-true}
+      - RUSTFS_PROF_CPU_MODE=${RUSTFS_PROF_CPU_MODE:-continuous}
+      - RUSTFS_PROF_CPU_FREQ=${RUSTFS_PROF_CPU_FREQ:-99}
+      - RUSTFS_PROF_OUTPUT_DIR=${RUSTFS_PROF_OUTPUT_DIR:-/tmp/rustfs-profiles}
+      - RUSTFS_OBJECT_MAX_CONCURRENT_DISK_READS=${RUSTFS_OBJECT_MAX_CONCURRENT_DISK_READS:-48}
+      - RUSTFS_OBJECT_IO_BUFFER_SIZE=${RUSTFS_OBJECT_IO_BUFFER_SIZE:-262144}
+      - RUSTFS_OBJECT_MEDIUM_CONCURRENCY_THRESHOLD=${RUSTFS_OBJECT_MEDIUM_CONCURRENCY_THRESHOLD:-6}
+      - RUSTFS_OBJECT_HIGH_CONCURRENCY_THRESHOLD=${RUSTFS_OBJECT_HIGH_CONCURRENCY_THRESHOLD:-12}
+      - RUSTFS_OBJECT_IO_RANDOM_READAHEAD_DISABLE_CONCURRENCY=${RUSTFS_OBJECT_IO_RANDOM_READAHEAD_DISABLE_CONCURRENCY:-8}
+      - RUSTFS_OBJECT_DUPLEX_BUFFER_SIZE=${RUSTFS_OBJECT_DUPLEX_BUFFER_SIZE:-8388608}
+      - RUSTFS_ERASURE_ENCODE_MAX_INFLIGHT_BYTES=${RUSTFS_ERASURE_ENCODE_MAX_INFLIGHT_BYTES:-25165824}
+      - RUSTFS_RUNTIME_WORKER_THREADS=${RUSTFS_RUNTIME_WORKER_THREADS:-12}
+      - RUSTFS_RUNTIME_MAX_BLOCKING_THREADS=${RUSTFS_RUNTIME_MAX_BLOCKING_THREADS:-512}
+      - RUSTFS_ALLOCATOR_RECLAIM_ENABLED=${RUSTFS_ALLOCATOR_RECLAIM_ENABLED:-false}
+    extra_hosts:
+      - "host.docker.internal:host-gateway"
+    volumes:
+      - node4_data_0:/data/rustfs0
+      - node4_data_1:/data/rustfs1
+      - node4_data_2:/data/rustfs2
+      - node4_data_3:/data/rustfs3
+    ports:
+      - "9003:9000"
+    networks:
+      - rustfs-cluster-net
+
+volumes:
+  node1_data_0:
+  node1_data_1:
+  node1_data_2:
+  node1_data_3:
+  node2_data_0:
+  node2_data_1:
+  node2_data_2:
+  node2_data_3:
+  node3_data_0:
+  node3_data_1:
+  node3_data_2:
+  node3_data_3:
+  node4_data_0:
+  node4_data_1:
+  node4_data_2:
+  node4_data_3:
+
+networks:
+  rustfs-cluster-net:
+    driver: bridge
@@ -90,6 +90,54 @@ docker compose down -v
 - **Grafana**: Dashboards and datasources are provisioned from the `grafana/` directory.
 - **Collector**: Edit `otel-collector-config.yaml` to modify pipelines, processors, or exporters.

+### Verifying RustFS Traces
+
+When RustFS points `RUSTFS_OBS_ENDPOINT` at this stack, treat the value as the
+OTLP/HTTP base URL, for example:
+
+```bash
+export RUSTFS_OBS_ENDPOINT=http://host.docker.internal:4318
+```
+
+RustFS automatically expands that base URL to:
+
+- `/v1/traces`
+- `/v1/metrics`
+- `/v1/logs`
+
+Important behavior notes:
+
+- Logs and metrics usually appear during startup, so seeing those two signals
+  first is expected.
+- Visible trace data usually requires real HTTP/S3/gRPC request traffic after
+  startup, because request-path spans are created on demand.
+- `RUSTFS_OBS_LOGGER_LEVEL=info` keeps the top-level request span but filters
+  many nested `debug` spans. If Tempo or Jaeger looks sparse, retry with
+  `RUSTFS_OBS_LOGGER_LEVEL=debug` before suspecting collector or Tempo issues.
+
+Minimal validation flow:
+
+```bash
+# 1. Start this observability stack.
+docker compose up -d
+
+# 2. Start RustFS with OTLP/HTTP export and richer span visibility.
+export RUSTFS_OBS_ENDPOINT=http://host.docker.internal:4318
+export RUSTFS_OBS_LOGGER_LEVEL=debug
+
+# 3. Generate real request traffic.
+curl -I http://127.0.0.1:9000/health
+curl -I http://127.0.0.1:9000/health/ready
+
+# 4. Inspect Grafana or Jaeger.
+# Grafana: http://localhost:3000
+# Jaeger:  http://localhost:16686
+```
+
+If logs and metrics are present but traces are sparse, the most common cause is
+"no real request traffic yet" or "`info` level filtered nested spans", not an
+OTLP routing failure.
+
 ## Troubleshooting

 - **Service Health**: Check the health of services using `docker compose ps`.
@@ -90,6 +90,50 @@ docker compose down -v
 -   **Grafana**: 仪表盘和数据源从 `grafana/` 目录预置。
 -   **Collector**: 编辑 `otel-collector-config.yaml` 以修改管道、处理器或导出器。

+### 验证 RustFS Trace
+
+当 RustFS 将 `RUSTFS_OBS_ENDPOINT` 指向这套技术栈时，应将该值视为
+OTLP/HTTP 的基础 URL，例如：
+
+```bash
+export RUSTFS_OBS_ENDPOINT=http://host.docker.internal:4318
+```
+
+RustFS 会自动在该基础 URL 后补全：
+
+- `/v1/traces`
+- `/v1/metrics`
+- `/v1/logs`
+
+需要注意：
+
+- 启动阶段通常会先看到日志和指标，因此“先有日志/指标、后有 trace”是正常现象。
+- 可见的 trace 数据通常依赖启动后的真实 HTTP/S3/gRPC 请求流量，因为请求路径上的 span 是按需创建的。
+- `RUSTFS_OBS_LOGGER_LEVEL=info` 会保留顶层请求 span，但会过滤掉很多 `debug` 级别的嵌套 span。
+  如果 Tempo 或 Jaeger 中的 trace 看起来很稀疏，建议先改成 `RUSTFS_OBS_LOGGER_LEVEL=debug`，再判断是否是 collector 或 Tempo 问题。
+
+最小验证流程：
+
+```bash
+# 1. 启动本目录下的可观测性技术栈。
+docker compose up -d
+
+# 2. 以 OTLP/HTTP 导出方式启动 RustFS，并提高 span 可见性。
+export RUSTFS_OBS_ENDPOINT=http://host.docker.internal:4318
+export RUSTFS_OBS_LOGGER_LEVEL=debug
+
+# 3. 产生真实请求流量。
+curl -I http://127.0.0.1:9000/health
+curl -I http://127.0.0.1:9000/health/ready
+
+# 4. 到 Grafana 或 Jaeger 中检查。
+# Grafana: http://localhost:3000
+# Jaeger:  http://localhost:16686
+```
+
+如果日志和指标已经正常，但 trace 仍然稀疏，最常见的原因通常是
+“还没有真实请求流量”或“`info` 级别过滤了嵌套 span”，而不是 OTLP 路由失败。
+
 ## 故障排除

 -   **服务健康**: 使用 `docker compose ps` 检查服务健康状况。