koko wrote:
rasz@capek:/etc$ cat /etc/hosts | grep 127 | uniq | wc -l
52076
rasz@capek:/etc$ sudo /etc/init.d/dnsmasq restart
rasz@capek:/etc$ cat /var/log/syslog
Oct 27 08:19:12 capek dnsmasq[8060]: exiting on receipt of SIGTERM
Oct 27 08:19:12 capek dnsmasq[8223]: started, version 2.33 cachesize 150
Oct 27 08:19:12 capek dnsmasq[8223]: compile time options: IPv6
GNU-getopt no-ISC-leasefile DBus I18N
Oct 27 08:19:12 capek dnsmasq[8223]: reading /etc/resolv.conf
Oct 27 08:19:12 capek dnsmasq[8223]: using nameserver 212.76.39.211#53
Oct 27 08:19:12 capek dnsmasq[8223]: using nameserver 212.76.39.205#53
Oct 27 08:19:12 capek dnsmasq[8223]: ignoring nameserver 127.0.0.1 -
local interface
Oct 27 08:24:55 capek dnsmasq[8223]: read /etc/hosts - 52076 addresses
Is this normal behaviour? this is 6 minutes of constant 100% cpu. Is
50k of entries just too much for it?
rasz@capek:/etc$ cat /proc/cpuinfo | grep Hz
cpu MHz : 2057.069
rasz@capek:/etc$ cat /proc/meminfo | grep mTo
MemTotal: 515868 kB
All of dnsmasq is written on the principle that premature optimisation
is the root of all evil. The /etc/hosts code is a good example: every
address read is checked against all the others to ensure that there is
no duplication of the reverse records. That's an instant n-squared
algorithm, which is fine for a few hundred entries, but not (it seems)
50000.
A question: are most of the addresses in your /etc/hosts the same, maybe
0.0.0.0 or 127.0.0.1, for ad-blocking? It seems a good quess that most
large /etc/hosts files would be of that form, and it's trivial to
optimse for that case.
Cheers,
Simon.
