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Re: Modify performance
Cannot upgrade but thanx for the pointer - i will start digging :)
However i am still wondering why is there such a significant
difference in performance between add and modify?
Isn't addition of a new entry also causing indexes to be rebuilt?
If so - how is that different from the modify in it's handling of indexes?
Howard Chu wrote:
Upgrade to OpenLDAP 2.1 and use back-bdb. You probably have indexing enabled
for several attributes. In OpenLDAP 2.0, on any modify, all attribute indices
for the entry are recomputed, even if most of those attributes are unchanged.
This generates enough churn that even with dbnosync, the page cache for the
database fills up quickly with dirty pages and needs to be flushed. In
OpenLDAP 2.1 back-bdb, only the indices of modified attributes are updated,
so much less I/O traffic is generated.
-- Howard Chu
Chief Architect, Symas Corp. Director, Highland Sun
Symas: Premier OpenSource Development and Support