We observed something similar after patching. A bunch of wxxx processes
generated huge load to reclaim the space used by deleted LOBs.
The default of _max_spacebg_slaves was huge - 1000 (?!), and we reduced it to
From: oracle-l-bounce@xxxxxxxxxxxxx <oracle-l-bounce@xxxxxxxxxxxxx> On Behalf
Of Jonathan Lewis
Sent: Donnerstag, 17. Juni 2021 12:41
To: ORACLE-L (oracle-l@xxxxxxxxxxxxx) <oracle-l@xxxxxxxxxxxxx>
Subject: Re: tablespace autoextend on next size not obeyed
Are these all bigfile tablespaces, do all the files have
dba_data_files.increment_by set explicitly to 10g (i.e. 1,310,720 if you're
using 8KB blocks).
Is the parameter "_enable_extent_preallocation" set to 3 on production and
Do the two systems have significantly different numbers of CPUs - which could
affect the number of Wnnn processes.
Do you get any clues about the small allocations being handled by foreground
processes while the large ones are handled by Wnnn?
I can't explain why you're seeing the effect, but I could imagine that even a
10G (unit) allocation being shared out in units of 64MB across multiple Wnnn
processes thanks to some algorithm that was checking concurrency, load, and CPU
Please consider the environment before printing this e-mail.
Bitte denken Sie an die Umwelt, bevor Sie dieses E-Mail drucken.
This message is intended only for the individual named. It may contain
confidential or privileged information. If you are not the named addressee you
should in particular not disseminate, distribute, modify or copy this e-mail.
Please notify the sender immediately by e-mail, if you have received this
message by mistake and delete it from your system.
Without prejudice to any contractual agreements between you and us which shall
prevail in any case, we take it as your authorization to correspond with you by
e-mail if you send us messages by e-mail. However, we reserve the right not to
execute orders and instructions transmitted by e-mail at any time and without
E-mail transmission may not be secure or error-free as information could be
intercepted, corrupted, lost, destroyed, arrive late or incomplete. Also
processing of incoming e-mails cannot be guaranteed. All liability of Vontobel
Holding Ltd. and any of its affiliates (hereinafter collectively referred to as
"Vontobel Group") for any damages resulting from e-mail use is excluded. You
are advised that urgent and time sensitive messages should not be sent by
e-mail and if verification is required please request a printed version.
Please note that all e-mail communications to and from the Vontobel Group are
subject to electronic storage and review by Vontobel Group. Unless stated to
the contrary and without prejudice to any contractual agreements between you
and Vontobel Group which shall prevail in any case, e-mail-communication is for
informational purposes only and is not intended as an offer or solicitation for
the purchase or sale of any financial instrument or as an official confirmation
of any transaction.
The legal basis for the processing of your personal data is the legitimate
interest to develop a commercial relationship with you, as well as your consent
to forward you commercial communications. You can exercise, at any time and
under the terms established under current regulation, your rights. If you
prefer not to receive any further communications, please contact your client
relationship manager if you are a client of Vontobel Group or notify the
sender. Please note for an exact reference to the affected group entity the
corporate e-mail signature. For further information about data privacy at
Vontobel Group please consult www.vontobel.com <https://www.vontobel.com>.