Log Metrics Generation Restrictions

This section describes the total rule quantity and constraints for LTS to generate metrics based on logs.

Figure 1 Total number of metric generation rules
Click to enlarge

**Table 1** Restrictions on metric generation
Category	Item	Description	Remarks
Metric generation	Total number of metric generation rules allowed in an account	By default, the maximum number of rules allowed for an account is 10, which is limited by the metadata at the software layer. NOTE: By default, one background task is allocated to each metric generation rule. The source log traffic that can be processed by a single background task is limited. If your source log traffic exceeds the limit, submit a service ticket to increase background tasks for each rule. If there are too many log generation metric rules and all background tasks are used up, some log generation metric rules will not be scheduled and executed.	N/A
	Steady log rate of one metric generation rule	≤ 40 MB/s (By default, one background task is assigned to one metric generation rule.)	If your source log traffic exceeds the limit, submit a service ticket to increase background tasks for each rule.
	Peak log rate of one metric generation rule	≤ 50 MB/s (By default, one background task is assigned to one metric generation rule.)	If your source log traffic exceeds the limit, submit a service ticket to increase background tasks for each rule.
	Parameters for configuring metric generation rules	Number of filter criteria groups ≤ 10; Number of associations in each group ≤ 10 Number of fields for group aggregation (Group By) ≤ 5 Cardinality of fields for group aggregation (Group By) ≤ 100	N/A
	Log time	The time difference between the log time and the LTS system time must be smaller than 1 hour. Otherwise, the task fails to be executed and metrics cannot be generated and reported to AOM.	The log time must be in order. If there is a severe time disorder or task timeout, logs cannot be processed. Typical example: If the time of the host where the collector is located is not synchronized with the NTP server time or log collection is severely delayed, the log time may be disordered, affecting the aggregation statistics for generated metrics.