cosbench-rs

cosbench-rs is a Rust implementation of the core COSBench workload model. It supports mock, S3, and Swift storage, staged concurrency, mixed operation ratios, integrity checks, multipart thresholds, and machine-readable reports.

Install and verify

cd cosbench-rs
cargo build --release --locked
./target/release/cosbench-rs --help
./target/release/cosbench-rs validate -c examples/swift-tempauth.yaml

Workload schema

Top-level fields are name, optional description, optional sample_interval_secs, storage, optional auth, and stages.

Storage types:

• mock: optional simulated latency_us;
• s3: endpoint, region, access/secret keys, path-style choice, timeout, and multipart threshold/part size;
• swift: storage endpoint, timeout, and optional static token.

Auth types are none, temp_auth, and keystone_v3. For Swift, an empty storage endpoint uses the URL returned by authentication.

name: swift-roundtrip
description: prepare, mixed read/write, then cleanup
sample_interval_secs: 1
auth:
  type: temp_auth
  url: http://127.0.0.1:8080/auth/v1.0
  user: test:tester
  key: REPLACE_FROM_SECRET_STORE
storage:
  type: swift
  endpoint: ""
  timeout_ms: 60000
stages:
  - name: main
    kind: main
    workers: 8
    runtime_secs: 30
    operations:
      - { type: read, ratio: 70 }
      - { type: write, ratio: 30 }
    objects:
      cprefix: bench-
      containers: { start: 1, end: 4 }
      oprefix: object-
      objects: { start: 1, end: 1000 }
      size: 65536
      hash_check: true

Each stage needs workers greater than zero, at least one operation with a nonzero total ratio, and either runtime_secs or total_ops. Write operations need a nonzero size or size_max. sequential: true makes object selection deterministic for prepare/cleanup-style stages.

Commands

cosbench-rs validate -c workload.yaml
cosbench-rs run -c workload.yaml --report-dir reports
cosbench-rs report -i reports --output reports/report.html
cosbench-rs import-xml -i legacy.xml -o workload.yaml
cosbench-rs serve --bind 127.0.0.1:19088

run writes JSON, CSV, and per-stage timeline CSV files when --report-dir is set. The HTML report is self-contained. Preserve the workload file and raw JSON beside derived CSV/HTML output.

Control server

serve provides /api/health, /api/workloads, /api/workloads/{id}, and /runs/{id}. Submitted work runs asynchronously in the process. The server’s CORS layer is permissive; bind it to loopback or a protected benchmark network and do not place storage credentials in browser-visible shared workloads.

Fair measurement

Separate prepare, measured main, and cleanup stages. Confirm the prepared population before interpreting read success. Record route, client placement, host contention, connection/concurrency settings, object distribution, errors, and p50/p95/p99. Route-labelled historical results are on Performance; G8 requirements are on G0-G8 validation.