On 04/02/17 21:35, A. Schulze wrote:
if i will run Debian, Postfix + Dovecot on a VPS Machine what i
need about memeory that this application can run without any
Problem, 256Mb are not enough?
works as long you avoid antivirus snakeoil and perl based spam
filtering.
Totally agree with this, then MySQL (or PG) are the next big ram
killers. If one can work with SQLite then I have tested small 256Mb
containers with 3 domains plus php7.1-fpm and got it down to around
120Mb of RSS (real) ram usage at almost idle... with spam filtering
using dovecot-antispam and spamprobe...
total used free shared buff/cache available
Mem: 262144 116128 146016 215336 0 146016
Swap: 675836 5980 669856
~ ps -eo rss:10,vsz:10,cmd --sort=rss | tail
7020 428928 /usr/sbin/opendkim -P [...]
7192 373420 php-fpm: master process
7500 145296 /usr/bin/perl -w /usr/sbin/mailgraph [...]
7616 373828 php-fpm: pool domain1
7684 373832 php-fpm: pool domain1
7712 373884 php-fpm: pool domain2
7804 373520 php-fpm: pool domain2
7904 373520 php-fpm: pool domain3
8124 374260 php-fpm: pool domain3
8232 374752 php-fpm: pool domain3
Of course if the websites need Wordpress then MySQL is mandatory
but even then, with a bit of tuning and by not using innodb, 2 or
3 lightly used vhost domains could (just) run in 256Mb ram and
quite easily survive in 512Mb ram (ie; a DO droplet.)
In contrast a "full service" mailcow install requires 800Mb at the
very least and 1Gb with some usage. Clamav is the real ram killer.
total used free shared buff/cache available
Mem: 1014064 696476 148480 8916 169108 170016
Swap: 1048572 169648 878924
And these are the top 10 ram users according to ps...
6088 393308 php-fpm: pool domain1
7184 94532 dovecot/dict
8028 395432 php-fpm: pool domain2
8028 395464 php-fpm: pool domain3
8812 85280 smtpd -t pass -u -o stress= -o [...]
26544 620088 /usr/sbin/mysqld
108120 207532 spamd child
108124 207532 spamd child
113140 207532 /usr/sbin/spamd -d [...]
481504 777468 /usr/sbin/clamd --foreground=true
And to the above I'd say roughly add about 1Gb ram per 50 users for
a real world web/mail hosting service.
