> -----Original Message----- > From: IBM Mainframe Discussion List > [mailto:[email protected]] On Behalf Of John Gilmore > Sent: Friday, June 22, 2012 7:27 AM > To: [email protected] > Subject: Re: Why is GRS ENQ needed in SMFDUMP program? > > Mostly, I don't see Shmuel's post, but this time he has commented on > one of mine. > > RESERVE is not a special form of ENQ. It was then and is now > hardware implemented. > > John Gilmore, Ashland MA 01721 - USA >
I am fairly sure that Shmuel's comment was about the RESERVE macro, not the hardware function. The RESERVE macro is logically equivalent to a SYSTEMS level ENQ plus a hardware reserve (unless the GRSRNL converts it to not do the hardware RESERVE). And, IIRC, the RESERVE macro generally does not immediately result in the hardware reserve being done before returning to the user. It simply marks the UCB somehow so that the hardware reserve is done at the beginning of the next I/O operation on the device. I'm not sure that this is still true or not. -- John McKown Systems Engineer IV IT Administrative Services Group HealthMarkets(r) 9151 Boulevard 26 * N. Richland Hills * TX 76010 (817) 255-3225 phone * [email protected] * www.HealthMarkets.com Confidentiality Notice: This e-mail message may contain confidential or proprietary information. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. HealthMarkets(r) is the brand name for products underwritten and issued by the insurance subsidiaries of HealthMarkets, Inc. -The Chesapeake Life Insurance Company(r), Mid-West National Life Insurance Company of TennesseeSM and The MEGA Life and Health Insurance Company.SM ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
