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databuff-proxy Dual-Write Stability

SkyWalking Agent dual-write via databuff-proxy under QPS=35: under 1 CPU core, ~47MB RSS, abnormal scenarios isolate cleanly — with 6-hour CPU/mem/network screenshots.

databuff-proxy · SkyWalking Agent dual-write · QPS=35 · report completed 2026-07-30

Migrating from SkyWalking to DataBuff can be a direct Agent retarget, or a databuff-proxy dual-write: point Agents once at the proxy, fan out to OAP and DataBuff, then leave SkyWalking after validation. This post is the dual-write load & stability report; steps live in From SkyWalking to DataBuff.

Test environment & write demo

ItemDetails
TopologyAgent (145) → proxy (120) → SkyWalking OAP (114) + DataBuff Ingest (113)
Proxydatabuff-proxy · listen :11800 · workers=8 · queue_size=4096
Write demoMicroservice call chain: 17 business services, 2 replicas each
MiddlewareRedis, MySQL, MongoDB, Kafka, etc. — 9 total
Total pods43 pods · write load QPS=35
UnitsProcess cores (not host-wide %) · span/s ≠ segment/s
Business write TPS
35
Same load on both sides
DataBuff ingest
11.3k
span/s
Same-QPS baseline
SkyWalking ingest
5.81k
segment/s
Same-QPS baseline
Per-path forwards
5838
req/s · symmetric · err/drop = 0
Proxy usage
0.89
cores (under 1) · RSS ~47 MB

Proxy host

CPU
16 vCPU
Memory
64 GiB
ScenarioCoresRSSNotes
Sustained full load~0.86~44 MBUnder 1 core
Overnight 10h+0.89~47 MBUnder 1 core · flat RSS

Figures are process cores, not host-wide CPU %.

~6-hour monitoring screenshots

proxy process CPU over 6 hours

Process CPU · ~5% ≈ 0.8 cores on 16-core host · flat

proxy process RSS over 6 hours

Process RSS · ~47–60 MB · no growth

host network receive over 6 hours

Host RX · steady traffic

host network transmit over 6 hours

Host TX · steady traffic

CPU/RSS from process detail; network from host120 (no process NIC metrics).

Abnormal scenarios

ScenarioHowBehaviorResult
One backend down DataBuff port unavailable Bad path circuits open; other path keeps writing; proxy stays up OK
Disable one write path Admin API toggle That path stops; other unaffected; re-enable recovers OK
Sustained high load QPS=35 continuous No drops / errors on either path OK
Long run 10h+ without stop Still forwarding; RSS flat OK
Restart after config Restart proxy Comes back and dual-writes again OK

Conclusion

CheckResult
Resource stability (under 1 core · flat RSS)Pass
Abnormal scenariosPass

Ready for production dual-write. See docs for both migration options; write throughput: Write Performance Comparison.

GitHub: https://github.com/databufflabs/databuff-proxy · Docs: Proxy Dual-Write Stability · Migration: From SkyWalking