RESOURCE_TRACE_RATIO Query Option (Impala 3.2 or higher only)
The RESOURCE_TRACE_RATIO
query option specifies the ratio of queries
where the CPU usage info will be included in the profiles. Collecting CPU usage and
sending it around adds a slight overhead during query execution. This query option lets
you control whether to collect additional information to diagnose the resource usage.
For example, setting RESOURCE_TRACE_RATIO=1
adds a trace of the CPU usage
to the profile of each query.
Setting RESOURCE_TRACE_RATIO=0.5
means that randomly selected half of all
queries will have that information collected by the coordinator and included in the
profiles.
Setting RESOURCE_TRACE_RATIO=0
means that CPU usage will not be tracked
and included in the profiles.
Values from 0 to 1 are allowed.
Type: Number
Default: 0
Added in: Impala 3.2