[389-devel] RFC: New Design: Fine Grained ID List Size

[David Boreham]

On 9/11/2013 11:41 AM, Howard Chu wrote:
>
> Just out of curiosity, why is keeping a count per key a problem? If 
> you're using BDB duplicate key support, can't you just use 
> cursor->c_count() to get this? I.e., BDB already maintains key counts 
> internally, why not leverage that?
>

afaik you need to pass the DB_RECNUM flag at DB creation time to get 
record counting behavior, and it imposes a performance and concurrency 
penalty on writes. Also afaik 389DS does not set that flag except on VLV 
indexes (which need it, and coincidentally were the original reason for 
the feature being added to BDB).