I think the ROT (rule of thumb) is that zero or near zero paging means that there is ample real storage. If there is paging, then zero or close demand page in rates indicate that there is no degradation.
Demand page in is synchronous which means that some workload(s) have to wait. Page out is asynchronous which means nothing waits for the action to complete and can be ignored. An average demand page in rate of, say, 5 per second is probably not noticeable and most likely means that your main storage is just right. Of course, most loved ones such as production CICS should be zero. That said, any non zero rate should be watched to make sure it does increase with workload growth. You might want more main if you have a lot of massive sorts. I'd be watchful for misguided attempts to constrain sort resources. SORT is generally well behaved and tries to be a good neighbor by default. Also, short term average observations made at peak demand may be more meaningful than long term averages. Short term averages would put transient spikes in a better perspective, I think. HTH and good luck. -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Chokalingam Thangavelu Sent: Tuesday, July 19, 2011 3:25 AM To: [email protected] Subject: Main memory usage Hi, We wanted to find out the Main memory usage of our production LPAR for a particular day. We have allocated 15GB of main memory and we wanted to find out this 15GB is enough or more memory need to added. We have printed RMF Paging activity report but is there any specific parameter needs to be looked at the paging report to find out the memory usage. Regards, Chokalingam Please do not print this email unless it is absolutely necessary. The information contained in this electronic message and any attachments to this message are intended for the exclusive use of the addressee(s) and may contain proprietary, confidential or privileged information. If you are not the intended recipient, you should not disseminate, distribute or copy this e-mail. Please notify the sender immediately and destroy all copies of this message and any attachments. WARNING: Computer viruses can be transmitted via email. The recipient should check this email and any attachments for the presence of viruses. The company accepts no liability for any damage caused by any virus transmitted by this email. www.wipro.com ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html NOTICE: This electronic mail message and any files transmitted with it are intended exclusively for the individual or entity to which it is addressed. The message, together with any attachment, may contain confidential and/or privileged information. Any unauthorized review, use, printing, saving, copying, disclosure or distribution is strictly prohibited. If you have received this message in error, please immediately advise the sender by reply email and delete all copies. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
