31 lines
1.5 KiB
Plaintext
31 lines
1.5 KiB
Plaintext
|
If you have a lot of groups or very large groups, cyrus-imapd login can become
|
||
|
|
quite slow due to the way cyrus-imapd handles groups. This may become worse
|
||
|
|
when using nss_ldap or other slow nss backends to resolve groups.
|
||
|
|
Caching using nscd can increase speed dramatically but unfortunately not for
|
||
|
|
all functions cyrus-imapd uses. nscd helps speeding up getgrnam() calls but not
|
||
|
|
getgrent() calls, which are used by cyrus-imapd to get a complete list of all
|
||
|
|
groups available.
|
||
|
|
The groupfile patch implements a quick fix to the problem by using a separate
|
||
|
|
group.cache file to speed up those operations using getgrent() calls.
|
||
|
|
Calls to getgrnam() are not touched which means that the group.cache
|
||
|
|
file must be kept in sync with the group source you are using with nss
|
||
|
|
configured in /etc/nsswitch.conf. If group.cache doesn't exist,
|
||
|
|
the patch has no effect and cyrus-imapd handles groups through getgrent().
|
||
|
|
|
||
|
|
Quick HOWTO:
|
||
|
|
- configure group lookup in /etc/nsswitch.conf if not already done
|
||
|
|
- configure name service cache in /etc/nscd.conf (not mandatory)
|
||
|
|
- start nscd with "service nscd start" (not mandatory)
|
||
|
|
- configure a service which periodically updates the group.cache file using the
|
||
|
|
upd_groupcache script. Either set up a cronjob or use a event in the cyrus
|
||
|
|
configuration.
|
||
|
|
|
||
|
|
Sample /etc/cyrus.conf event to update the group cache every 10 minutes:
|
||
|
|
EVENTS {
|
||
|
|
# some events removed here ***
|
||
|
|
...........................***
|
||
|
|
|
||
|
|
# this is only necessary if using group cache feature
|
||
|
|
groupcache cmd="upd_groupcache" period=10
|
||
|
|
}
|