ownCloud causes 100% CPU on LDAP(samba4)-Server

we just made an upgrade from owncloud v9.09 to v9.1.5. owncloud-authentication is based on ldap. Our ldap-server is a samba4-server, which simulates an AD.
owncloud is very very slow, but the owncloud-server itself has actually nothing to do (no cpu load, no ram using). The problem is, that owncloud causes a 100% cpu-load on the ldap-server and this with less than 10 users being active. So a ldap-user needs minutes only to login, on the contrary a local owncloud-user needs just some seconds.

can it be that the "ldap-backend"-app has a problem ? I'm thinking this, because with our new version we are not able to delete ldap-users from owncloud anymore - users, who dont exist in ldap anymore but still in the owncloud-db. the occ-tool says " is not a valid user anymore".

why this cpu-load on the ldap-server ? what is owncloud doing ?
We really need help as quick as possible, because right now owncloud is not usable.

thanks in advance


Hi Thomschu,

thank you for reporting this. I don't really know about the load issues. Maybe you could report an complete issue @ https://github.com/owncloud/user_ldap/issues with a detailed description of your setup?

Did you try https://doc.owncloud.org/server/9.0/admin_manual/configuration_user/user_auth_ldap_cleanup.html?highlight=ldap#ldap-user-cleanup
and here especially?

sudo -u www-data php occ ldap:show-remnants displays a table with all users that have been marked as deleted, and their LDAP data.
sudo -u www-data php occ user:delete [user]

Please also note that the user_ldap is currently under a major rework and a new improved version should be available in 3-4 weeks.