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Re: fast delete a lot of entries

Hi Derek,

no idea about the deletion speed, but if a short downtime is an option
and the entries to be deleted can be matched by a search filter, you
could do a

  slapcat -a '(!(<filter of what should be deleted>))'

and the slapadd the resulting file into an empty database. Depending
on the amount of to entries be deleted in comparison to the total
number of entries in the database, this could be quicker than live
deletes.

best regards
Karsten
Am Sa., 24. Nov. 2018 um 18:56 Uhr schrieb Derek Zhou <derek@shannon-data.com>:
>
> dear list,
>
> I was experimenting with slapd by adding a lot of entries then deleting them. What I found is adding speed is not bad but deletion speed is lacking. With or without dbsync, delete speed is around half of that of adding. Naively, I thought deleting should be easier than adding, because in adding you actually need to pass and write whole entry of data, while in delete you can just mark the database page as free? The DB file did not shrink after massive deletion; which kind of suggest that deleting is only marking page as free, not really return them to the OS. I am using the latest git tree and the mdb backend.
>
> Another related idea is delete a whole branch from the DIT. LDAP is already hierarchical, to delete all entries under a branch, one would assume that there must be an better way than deleting entries with a client side script, like what I am doing? With SQL you can drop a table. With LDAP, can I delete a whole branch?
>
> --
> Derek Zhou
> Shannon Systems
> http://www.shannon-sys.com
>