Running out of memory will prevent the Linux system from running ZCS because it can’t create the needed Java virtual machine and also start essential processes like the MTA. During the installation I came to several situations where I ran out of memory but in the end I could install the software but not start all services. I needed some optimization here. After some searching on the web I found tips which helped me.

Unused or unneeded services should be shutdown first. You’ve to decide if you need the logger, which offers data about sent and received mails and so on, or the antivirus and anti spam services. After that you’ve to play with the Java and 3rd party component memory settings. On the Zimbra Wiki there are some community contributed articles which helped me. They talk about increasing the Tomcat heal size, lowering the MySQL memory usage and more. I’ll give you the parameters I’ve used:

zmlocalconfig -e tomcat_java_heap_memory_percent=40

zmlocalconfig -e tomcat_java_heap_memory_percent=40

zmlocalconfig -e zmmtaconfig_interval=3600
zmlocalconfig -e zmstat_interval=300
zmlocalconfig -e mailboxd_java_heap_memory_percent=10
zmlocalconfig -e mailboxd_java_heap_new_size_percent=10

zmlocalconfig -e mailboxd_java_options="-server -Djava.awt.headless=true -XX:+UseConcMarkSweepGC -XX:NewRatio=2 -XX:PermSize=128m \
-XX:MaxPermSize=128m -XX:SoftRefLRUPolicyMSPerMB=1"

zmlocalconfig -e ldap_common_threads=16
zmlocalconfig -e ldap_common_toolthreads=8
zmlocalconfig -e ldap_db_cachesize=50000
zmlocalconfig -e ldap_db_idlcachesize=50000
zmlocalconfig -e ldap_db_dncachesize=0
zmprov mcf zimbraMessageCacheSize 5000

Change the my.cnf file in /opt/zimbra/conf:

thread_cache = 5

maxconnections = 15

innodb_buffer_pool_size = 144245094

Change the slapd.conf.in also be found in /opt/zimbra/conf:

threads 8

idletimeout 5

Edit the /opt/zimbra/conf/amavisd.conf.in file:

$max_servers = 1;

This parameter will only start one server instance for the antivirus/anti spam service. By default it’s 10.

Be careful with the config file names! Always use the *.in file if it is there. During startup the server will overwrite the *.conf file with the *.conf.in file.

All information here is officially not supported with the ZCS Network Edition as it says on the Zimbra Wiki.

Similar Posts:

• Important commands you’ll need for Zimbra
• Preparing Ubuntu and Install Zimbra CS
• Configuring Zimbra Desktop with a ZCS
• Zimbra Desktop 7 Beta: Unable to unmarshal response for AuthResponse
• Zimbra: Hello world!