Option Name:netdb_low
Default Value:netdb_low 900
Suggested Config:

	The low water mark for the ICMP measurement database.

	Note: high watermark controlled by netdb_high directive.

	These watermarks are counts, not percents.  The defaults are
	(low) 900 and (high) 1000.  When the high water mark is
	reached, database entries will be deleted until the low
	mark is reached.