This directive specifies the number of delay pools that you will later define with the delay_class and delay_parameters directives. It tells Squid the size of certain arrays used in the delay pools implementation. It must appear in the configuration file before the other delay pools directives.
Note that in order to use delay pools, you must give the
—enable-delay-pools option to ./configure.
delay_class, delay_access, delay_parameters, delay_initial_bucket_level