[Dnsmasq-discuss] How may is too many CNAME references?

[Ercolino de Spiacico]

See these two test here below.
TEST1: the dnsmasq.adblockFULL contains about 15.9K CNAME records. I'm 
generating the wanted dnsmasq.adblock file with an increased number of 
records. The test is essentially parsing the file and benchmarking them. 
As you can see there's something happening after 3000/4000 records as 
the time required is not linear.


root at sparrow:/tmp/etc# head -1200 ./dnsmasq.adblockFULL  > ./dnsmasq.adblock
root at sparrow:/tmp/etc# time dnsmasq --test
dnsmasq: syntax check OK.
real    0m 0.14s
user    0m 0.14s
sys     0m 0.00s
root at sparrow:/tmp/etc# head -3000 ./dnsmasq.adblockFULL  > ./dnsmasq.adblock
root at sparrow:/tmp/etc# time dnsmasq --test
dnsmasq: syntax check OK.
real    0m 1.01s
user    0m 1.00s
sys     0m 0.00s
root at sparrow:/tmp/etc# head -4000 ./dnsmasq.adblockFULL  > ./dnsmasq.adblock
root at sparrow:/tmp/etc# time dnsmasq --test
dnsmasq: syntax check OK.
real    0m 3.40s
user    0m 3.38s
sys     0m 0.01s
root at sparrow:/tmp/etc# head -5000 ./dnsmasq.adblockFULL  > ./dnsmasq.adblock
root at sparrow:/tmp/etc# time dnsmasq --test
dnsmasq: syntax check OK.
real    0m 7.48s
user    0m 7.46s
sys     0m 0.01s
root at sparrow:/tmp/etc# head -6000 ./dnsmasq.adblockFULL  > ./dnsmasq.adblock
root at sparrow:/tmp/etc# time dnsmasq --test
dnsmasq: syntax check OK.
real    0m 12.67s
user    0m 12.61s
sys     0m 0.02s
root at sparrow:/tmp/etc# head -7000 ./dnsmasq.adblockFULL  > ./dnsmasq.adblock
root at sparrow:/tmp/etc# time dnsmasq --test
dnsmasq: syntax check OK.
real    0m 19.10s
user    0m 19.05s
sys     0m 0.01s
root at sparrow:/tmp/etc# head -15000 ./dnsmasq.adblockFULL  > 
./dnsmasq.adblock
root at sparrow:/tmp/etc# time dnsmasq --test
dnsmasq: syntax check OK.
real    1m 43.89s
user    1m 43.57s
sys     0m 0.09s


TEST2:  In this second test the adblock is defined using address= (so A 
records):

root at sparrow:/tmp/etc# wc -l /etc/dnsmasq.adblock
15966 /etc/dnsmasq.adblock
root at sparrow:/tmp/etc# time dnsmasq --test
dnsmasq: syntax check OK.
real    0m 0.14s
user    0m 0.13s
sys     0m 0.01s