Michael Ströder michael@stroeder.com schrieb am 19.08.2019 um 10:44 in
Nachricht 27f4384a-5d12-c6b3-3e1d-f85400e2a84a@stroeder.com:
On 8/19/19 9:24 AM, Ulrich Windl wrote:
Michael Ströder michael@stroeder.com schrieb am 17.08.2019 um 20:37
in
Nachricht 123c2421-b539-14cb-6c82-44235675b5cd@stroeder.com:
On 8/17/19 2:52 PM, Marc Roos wrote:
Over time I am adding indexes until there are no such messages (except for some incidental queries).
And that's exactly the wrong thing to do! That's why I requested to disable those messages in ITS#7796:
https://www.openldap.org/its/index.cgi?findid=7796
By adding random indexes just to get rid of not-indexed warnings you can dramatically lower your search performance. You should only add an index if you analyzed that clients send search requests with filters which can make good use of the index.
I agree that some thinking before adding an index isn't a bad idea, but
still
I think these messages are important as they can make you start thinking.
Experience shows that people do not analyse the LDAP filters but just add an index to get rid of the message. You can find that many times in various discussion / Q&A forums.
It's also bad that this message is written at any loglevel. Depending on your config it can be written many times for the same attribute during processing a single search operation, e.g. when processing the numerous set-based ACLs in my Æ-DIR. 50+ senseless log lines for a single search operation with deref control is not fun.
I could imagine that either...
* writing each message only once since slapd started * suppressing each message for a configurable time interval (like 1 hour, 1 day, 1 week, etc.)
... would be a solution people could live with.
As for the case: Can you present an example here where an index added as suggested makes performance actually worse?
Ciao, Michael.