trace_profile_events_* session settings

These settings are available in system.settings and are autogenerated from source.

trace_profile_events

Enables or disables collecting stacktraces on each update of profile events along with the name of profile event and the value of increment and sending them into trace_log.

Possible values:

• 1 — Tracing of profile events enabled.
• 0 — Tracing of profile events disabled.

trace_profile_events_list

When the setting trace_profile_events is enabled, limit the traced events to the specified list of comma-separated names. If the trace_profile_events_list is an empty string (by default), trace all profile events.

Example value: ‘DiskS3ReadMicroseconds,DiskS3ReadRequestsCount,SelectQueryTimeMicroseconds,ReadBufferFromS3Bytes’

Using this setting allows more precise collection of data for a large number of queries, because otherwise the vast amount of events can overflow the internal system log queue and some portion of them will be dropped.