Session traffic
Open Traffic from a session to access Log replay and, when enabled for the workspace, Load test. Replay requires an operator role. Load testing is available only when the tenant setting permits it.
Replay a log
Choose the replay direction before pasting a log or selecting a file. The panels accept SOH, ^A, and pipe separators. Preview the classified messages before starting a replay.
Outbound sends application messages on the live FIX connection. The session must be logged on. Session-control messages are refused to protect the active session. Select Preserve retransmission metadata only when the capture needs its retransmission fields retained.
Inbound runs a shadow analysis. It copies the current session configuration into an isolated, disposable order book and does not touch the live FIX connection or live state. It accepts client-side executable application messages and generates the simulator responses for analysis. Simulator responses and session-control messages in a capture are not inputs to that analysis.
Use Remove session-layer messages before replaying a capture dominated by heartbeats or logon traffic. The preview identifies sendable or replayable messages, refused messages, unsupported messages, and invalid lines. An inbound analysis can be stopped while it is running; its report includes generated responses and virtual elapsed time.
Outbound replay places messages on the wire. Start with a small, reviewed application-only capture and inspect the result in Blotter Out.
Run a load test
Select Blast to emit synthetic outbound traffic, or Amplify to produce a configured number of synthetic fills for each inbound order. Set the rate and duration, and set the amplification factor for Amplify, then select Start.
The panel reports running status, elapsed time, messages and bytes sent, configured rate, and remaining byte budget. A tenant can run one load test on a session at a time. Stop the run from the same panel and check the outgoing blotter and client behaviour before increasing load.
The server validates the permitted rate, duration, burst capacity, tenant status, and daily budget. If a request is refused, keep the session ID and UTC time with the displayed error for the operator who manages load-testing access.
Updated 2026-09-10 · Edit on GitHub