ca.portal.admin

Deadlock Detection Interval

Discussion created by ca.portal.admin on Oct 4, 2007
Latest reply on Oct 4, 2007 by ca.portal.admin
Has anybody done any benchmarks on how much CPU the Deadlock Detection
mechanism uses?

I have the interval set to 1 and so deadlocks are detected pretty much
immediately. But am I spending lots of CPU unneccessarily? I mean if someone
is going to deadlock and get rolled out does it really matter if it happens
in the next 0.5 seconds or 5 seconds on average.

We think we have a lot of deadlocks but actually compared to the number of
transactions it is really small - perhaps 1 an hour. So in 1 hour with DDI =
1 the CV checks 3600 times and only detects a problem once.

I'm sure there is some overhead, but does anyone know how much? Is it worth
playing with it?

I am R15.0 SP7 Z/OS.


An aside: I met a Lesbian DBA at a party at the weekend. Naturally I was
horrified and disgusted and decided she needed converting. But after 3 hours
of my preaching and me buying 4 Southern Comforts and lemonade for her, she
still believed that DB2 was better. Does anyone know how to recognise a
relational model DBA from a distance? Can I claim the cost of the drinks
from the IUA?

______________________________________________________________

Chris Trayler, IXD
Bank Julius Baer & Co. Ltd.
P. O. Box, CH-8010 Zürich, Switzerland
Telephone +41 (0)58 887 4332, Fax +41 (0)58 887 4969
www.juliusbaer.com <http://www.juliusbaer.com/>

______________________________________________________________

*****JuliusBaer Disclaimer***** This message is for the addressee only and
may contain confidential or privileged information. You must delete and not
use it if you are not the intended recipient. It may not be secure or
error-free. All e-mail communications to and from the Julius Baer Group may
be monitored. Processing of incoming e-mails cannot be guaranteed. Any views
expressed in this message are those of the individual sender. This message
is for information purposes only. All liability of the Julius Baer Group and
its entities for any damages resulting from e-mail use is excluded. US
persons are kindly requested to read the important legal information
presented at following URL: http://www.juliusbaer.com/maildisclaimer


"
IDMS Public Discussion Forum
IDMS-L@LISTSERV.IUASSN.COM
SMTP
IDMS-L@LISTSERV.IUASSN.COM
IDMS-L@LISTSERV.IUASSN.COM
SMTP








Normal

Normal
Deadlock Detection Interval
"Has anybody done any benchmarks on how much CPU the Deadlock Detection mechanism uses?

I have the interval set to 1 and so deadlocks are detected pretty much immediately. But am I spending lots of CPU unneccessarily? I mean if someone is going to deadlock and get rolled out does it really matter if it happens in the next 0.5 seconds or 5 seconds on average.

We think we have a lot of deadlocks but actually compared to the number of transactions it is really small - perhaps 1 an hour. So in 1 hour with DDI = 1 the CV checks 3600 times and only detects a problem once.

I'm sure there is some overhead, but does anyone know how much? Is it worth playing with it?

I am R15.0 SP7 Z/OS.


An aside: I met a Lesbian DBA at a party at the weekend. Naturally I was horrified and disgusted and decided she needed converting. But after 3 hours of my preaching and me buying 4 Southern Comforts and lemonade for her, she still believed that DB2 was better. Does anyone know how to recognise a relational model DBA from a distance? Can I claim the cost of the drinks from the IUA?

______________________________________________________________

Chris Trayler, IXD
Bank Julius Baer & Co. Ltd.
P. O. Box, CH-8010 Zürich, Switzerland
Telephone +41 (0)58 887 4332, Fax +41 (0)58 887 4969
www.juliusbaer.com <http://www.juliusbaer.com/>

______________________________________________________________

*****JuliusBaer Disclaimer***** This message is for the addressee only and may contain confidential or privileged information. You must delete and not use it if you are not the intended recipient. It may not be secure or error-free. All e-mail communications to and from the Julius Baer Group may be monitored. Processing of incoming e-mails cannot be guaranteed. Any views expressed in this message are those of the individual sender. This message is for information purposes only. All liability of the Julius Baer Group and its entities for any damages resulting from e-mail use is excluded. US persons are kindly requested to read the important legal information presented at following URL: http://www.juliusbaer.com/maildisclaimer
"
IDMS Public Discussion Forum
IDMS-L@LISTSERV.IUASSN.COM
SMTP
IDMS-L@LISTSERV.IUASSN.COM
IDMS-L@LISTSERV.IUASSN.COM
SMTP








Normal

Normal
Re: batch ACCEPT SYSVERSION
"While we know that ACCEPT SYSVERSION is an IDMS-DC construct that only
works when actually running inside the IDMS region - it is useful to
know which CV a batch program is running against. If running in local
mode you would need something in the database - as previously suggested.


What we do in CV mode is call a program that accesses the dataset name
of the SYSCTL file - and based on its name it returns a ""sysversion"" -
derived based on known naming standards. This has worked well for us -
could probably share the code if that would help.

HTH - cheers - Gary

Gary Cherlet
Justice Technology Services
Department of Justice, SA Government
Telephone +61 (0)8 8226 5199
Facsimile +61 (0)8 8226 5311
Mobile +61 (0)41 333 1613
MailTo:cherlet.gary@saugov.sa.gov.au

This e-mail message and any attachments are qualified as follows:
Addressing: If you have received this e-mail in error, please advise by
reply e-mail to the sender. Please also destroy the original
transmission and its contents. Confidentiality: This e-mail may contain
confidential information which also may be legally privileged. Only the
intended recipient(s) may access, use, distribute or copy this e-mail.
Individual Views: Unless otherwise indicated, the views expressed are
those of the sender, not Justice Technology Services. Computer Viruses:
It is the recipient's responsibility to check the e-mail and any
attached files for viruses.

Outcomes