Delay in queue call distribution

Hi team,

We have a queue, which has now delay in call distribution. ring strategy is rrmemory without autofil.
After googling we found the option called autofill=yes earlier it was no.

In the google people said after enabling autofill = yes; calls will be distributed without delay. Kindly provide us any suggestion apart from below.

[500]
announce-frequency=75
announce-holdtime=yes
announce-position=no
autofill=yes
eventmemberstatus=no
eventwhencalled=yes
joinempty=yes
leavewhenempty=no
maxlen=0
monitor-type=mixmonitor
monitor-format=wav
music=MCI
periodic-announce-frequency=0
queue-callswaiting=silence/1
queue-thereare=silence/1
queue-youarenext=silence/1
reportholdtime=no
retry=5
ringinuse=no
servicelevel=15
strategy=rrmemory
timeout=15
weight=0
wrapuptime=0

Thanks,
Ashik