Slow connections with 12.2 client

Has anybody else observed initial connectivity with the 12.2 windows client to be significantly slower than in 12.1 (or 11.2). My setup has ldap and TNS_ADMIN involved.

12.1
ORACLE_HOME: C:\APP\ORACLE\INSTANTCLIENT_12_1 TNS_ADMIN: C:\APP\TNS 12.2
ORACLE_HOME: C:\APP\ORACLE\INSTANTCLIENT_12_2 TNS_ADMIN: C:\APP\TNS Extract from an admin level sqlnet trace in 12.1

(12180) [29-MAY-2018 14:53:56:171] nnflgetnlpactx: NLPA context successfuly
initialized
(12180) [29-MAY-2018 14:53:56:172] nnflgetnlpactx: exit
(12180) [29-MAY-2018 14:53:56:517] nnfloidinfocache: entry
(12180) [29-MAY-2018 14:53:56:517] nnfloidinfocache: Info: Inserted value
DIRECTORY_SERVER_TYPE=OID at index 0 into NLPA_CACHE

and from 12.2

(9712) [29-MAY-2018 14:47:01:777] nnflgetnlpactx: NLPA context successfuly
initialized
(9712) [29-MAY-2018 14:47:01:777] nnflgetnlpactx: exit
(9712) [29-MAY-2018 14:47:38:195] nnfloidinfocache: entry
(9712) [29-MAY-2018 14:47:38:195] nnfloidinfocache: Info: Inserted value
DIRECTORY_SERVER_TYPE=OID at index 0 into NLPA_CACHE

Note the extra 30 secs between exit from the nnflgetnlpactx function and entry to the OID related function nnfloidinfocache

I have a ticket with Oracle Support but wondered if anyone else has seen this.

-- 
Niall Litchfield
Oracle DBA
http://www.orawin.info

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