Memory allocator

Package installations use jemalloc as memory allocator for all Zammad Ruby processes, as recommended by Rails. This reduces memory usage and fragmentation. The package postinstall script preloads the jemalloc library automatically if it's present on your system. This happens on every package installation and upgrade.

Docker installations have jemalloc enabled by default (baked into the image). To opt out, override the environment variable with an empty value (e.g. LD_PRELOAD="" in your compose or env file).

Availability

• Debian and Ubuntu: libjemalloc2 is installed automatically as package dependency.
• CentOS and RHEL: jemalloc is installed automatically from the EPEL repository (already a Zammad dependency).
• SLES: jemalloc is not installed automatically (available via SUSE Package Hub or SLE modules). If you install it manually with zypper install jemalloc, Zammad activates it automatically on the next package installation or upgrade.

Opt-out and opt-in

To opt out of using jemalloc:

zammad config:set ZAMMAD_USE_JEMALLOC=no

This takes effect on the next package installation or upgrade. The postinstall script then removes the LD_PRELOAD variable entirely, so a pre-existing system value is respected. For immediate effect:

zammad config:unset LD_PRELOAD

systemctl старт заммад

To opt back in, unset the variable again (any value other than no re-enables jemalloc on the next package installation or upgrade):

zammad config:unset ZAMMAD_USE_JEMALLOC

To verify whether jemalloc is active, run:

zammad run ruby -e 'puts File.read("/proc/self/maps").match?(/jemalloc/) ? "jemalloc active" : "jemalloc NOT active"'