Re: Memory need for upgrade to 18c

From: Stefan Koehler <>
Date: Fri, 17 May 2019 09:42:31 +0200 (CEST)
Message-ID: <>

Hello Thanh,
ah AIX and Oracle is like Tom and Jerry ;-)

Maybe the good old "USLA heap" problem is back again. However if you have not changed any parameter (e.g. SGA_TARGET, MEMORY_TARGET, PGA_AGGREGATE_TARGET) and you are not using more (over-allocated) PGA than before than it is very likely caused by heap memory consumption of each Oracle process - you can check the memory and break it down with "svmon" very easily ( ).

Best Regards
Stefan Koehler

Independent Oracle performance consultant and researcher Website:
Twitter: _at_OracleSK

> Thanh NGUYEN <> hat am 16. Mai 2019 um 21:31 geschrieben:
> Hello,
> Aix 7.2 ML03
> We upgraded 5 instances from to 18c, without changing any
> parameter.
> Then we observed that memory is used more than before the upgrade,
> nearly 2GB more for each.
> Do you have any experience/explanation about that please?
> Thank you in advance.
> Best regards,
> Thanh NGUYEN
> --

Received on Fri May 17 2019 - 09:42:31 CEST

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