Performance Schema System Variables Dynamic No SET_VAR  Hint Applies No Type Integer Default Value -1  (signifies autoscaling; do not assign this literal value) Command-Line Format --performance-schema-max-digest- length=# System Variable performance_schema_max_digest_length Scope Global Dynamic No SET_VAR  Hint Applies No Type Integer Default Value 1024 Minimum Value 0 Maximum Value 1048576 Command-Line Format --performance-schema-max-digest- sample-age=# System Variable performance_schema_max_digest_sample_age Scope Global Dynamic Yes SET_VAR  Hint Applies No Type Integer Default Value 60 Minimum Value 0 Maximum Value 1048576 This variable affects statement sampling for the  events_statements_summary_by_digest  table. When a new table row is inserted, the statement that produced the row digest value is stored as the current sample statement associated with the digest. Thereafter, when the server sees other statements with the same digest value, it determines whether to use the new statement to replace the current sample statement (that is, whether to resample). Resampling policy is based on the comparative wait 5107 The maximum number of bytes of memory reserved per statement for computation of normalized statement digest values in the Performance Schema. This variable is related to  max_digest_length ; see the description of that variable in Section 5.1.8, “Server System Variables” . For more information about statement digesting, including considerations regarding memory use, see Section 27.10, “Performance Schema Statement Digests and Sampling” . • performance_schema_max_digest_sample_age The maximum number of instrumented condition objects. For information about how to set and use this variable, see Section 27.7, “Performance Schema Status Monitoring” . • performance_schema_max_digest_length