the configure file  as follows:

options { use_dns(no); create_dirs(yes);ts_format(iso); };

#options { log_fifo_size(3000); };

source src { udp(ip(0.0.0.0) port(514) ); };

 

filter f_kern { facility(kern); };

filter f_authpriv { facility(auth,authpriv); };

filter f_mail { facility(mail); };

filter f_cron { facility(cron); };

filter f_boot { facility(local7); };

filter f_spooler { facility(uucp, news) and level(crit..emerg); };

filter f_messages { level(info..emerg) and not facility(authpriv, cron, mail); };

 

destination kern { file("/home/syslog-ng/$YEAR/$HOST/kernel-$MONTH"); };

destination authpriv { file("/home/syslog-ng/$YEAR/$HOST/secure-$MONTH"); };

destination mail { file("/home/syslog-ng/$YEAR/$HOST/maillog-$MONTH"); };

destination cron { file("/home/syslog-ng/$YEAR/$HOST/cron-$MONTH"); };

destination boot { file("/home/syslog-ng/$YEAR/$HOST/boot.log-$MONTH"); };

destination spooler { file("/home/syslog-ng/$YEAR/$HOST/spooler-$MONTH"); };

destination messages { file("/home/syslog-ng/$YEAR/$HOST/messages-$MONTH"); };

 

 

log { source(src); filter(f_kern); destination(kern); };

log { source(src); filter(f_authpriv); destination(authpriv); };

log { source(src); filter(f_mail); destination(mail); };

log { source(src); filter(f_cron); destination(cron); };

log { source(src); filter(f_boot); destination(boot); };

log { source(src); filter(f_spooler); destination(spooler); };

log { source(src); filter(f_messages); destination(messages); };

syslog-ng receive logs from about 1000 clients ,and the usage of mem by syslog-ng keeps growing,here are a days record of the usage of mem(got by command ‘ps aux’):

cup %mem

0.1 29.9

0.1 30.1

0.1 30.3

0.1 30.5

0.1 30.7

0.1 30.9

0.1 31.1

0.1 31.2

0.1 31.4

0.1 31.6

0.1 31.9

0.1 32.1

0.1 32.3

0.1 32.4

0.1 32.6

0.1 32.8

0.1 33.0

0.1 33.2

0.1 33.4

0.1 33.5

0.1 33.8

0.1 33.9

0.1 34.1

0.1 34.3

0.1 34.5

0.1 34.6

0.1 34.9

0.1 35.0

0.1 35.2