Does anybody hear remember a software product from a Russian company that allowed one to run Linux as an address space under OS/390? If memory serves me correctly, I think this was in the 1990's, possible early 2000's.
-----Original Message----- From: IBM Mainframe Discussion List <[email protected]> On Behalf Of Phil Smith III Sent: Thursday, April 21, 2022 2:26 PM To: [email protected] Subject: Re: Use of zCX [External Email. Exercise caution when clicking links or opening attachments.] >It likes a LOT of real memory and it appears that the running instance consumes the full amount of real memory allocated to it for the duration, making it unavailable to zOS for paging or any other use. Well, sure-that memory use is Linux caching files in memory. This has all been explored, analyzed, and solved under z/VM years ago; alas, z/OS doesn't have the same kinds of controls, so it's going to be a problem with zCX until and unless IBM adds some knobs. I'm with Dave Jones re "Where's the real value?" I remember when IBM first proposed what became zCX, I asked what the point was. The answer I got was "It's politically hard/impossible to get an LPAR created to run z/VM (not to mention paying for z/VM) or to run Linux on the bare iron". A technical solution to a political problem is painful to contemplate, but is sometimes necessary, and it appears that's what zCX is. Running an entire operating system under z/OS that isn't acclimated to doing so is inherently problematic. Things like Db2 and CICS have spent many, many years being made into good z/OS citizens (OK, since CICS has always been under z/OS and predecessors, that's obvious-but Db2 started as SQL/DS on VM). Sure, IBM can make Linux behave under z/OS, but it's gonna take a while! And the real value is still unclear to me, beyond the political hurdles. You're sure not going to run hundreds of zCX containers under z/OS, I don't think, as you can Linuxen under z/VM. TonyH: My information is that z/OS (MVS) only uses SIE for zCX, so I think that's just two levels of SIE, which presumably/hopefully means vSIE, which isn't that bad? ...phsiii (who spent four years doing Linux provisioning under z/VM at Linuxcare and then a few years doing performance of Linux under z/VM, so feels he has some qualifications to make the above assertions) ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN Confidentiality notice: This e-mail message, including any attachments, may contain legally privileged and/or confidential information. If you are not the intended recipient(s), or the employee or agent responsible for delivery of this message to the intended recipient(s), you are hereby notified that any dissemination, distribution, or copying of this e-mail message is strictly prohibited. If you have received this message in error, please immediately notify the sender and delete this e-mail message from your computer. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
