Is it normal for opendkim process to use 1GB Ram ?

Virtualmin on Debian 8 server

When I check the memory system information, I can see the opendkim is one of the most consuming ram process. It use 980MB while my whole system has only 4GB of Ram. Is it a normal thing? Can I reduce/limit its usage? Thanks

Please check two things:

  1. Check openDKIM version and origin by executing repoquery -i opendkim. If this command doesnt work then you will need to install yum-utils. Here is the example from my server:
    [root@XXXXXX ~]# repoquery -i opendkim
    Name : opendkim
    Version : 2.11.0
    Release : 0.1.el7
    Architecture: x86_64
    Size : 603312
    Packager : Fedora Project
    Group : System Environment/Daemons
    URL : http://opendkim.org/
    Repository : epel
    Summary : A DomainKeys Identified Mail (DKIM) milter to sign and/or verify mail
    Source : opendkim-2.11.0-0.1.el7.src.rpm
    Description :
    OpenDKIM allows signing and/or verification of email through an open source
    library that implements the DKIM service, plus a milter-based filter
    application that can plug in to any milter-aware MTA, including sendmail,
    Postfix, or any other MTA that supports the milter protocol.

  2. Check the logs for any trace of openDKIM complaining about something.

This is for Centos so you will need to find the right commands for your OS.

There was similar problem with openDKIM like yours and the reason was a memory leak, but this was patched long time ago.