On Wednesday, 05/23/2018 at 05:08 GMT, Philipp Kern <[email protected]> wrote: > On 2018-05-23 08:57, Paul Edwards wrote: > > I would think that most ELF32 programs are already > > able to use the full 4 GiB address space without > > needing a recompile. malloc() can start returning > > addresses in the 2 GiB - 4 GiB range. > > Traditionally this is untrue on s390 because -m31 produces 31bit code > that cannot access more than 2GB of virtual memory. Is -m32 even a thing > on s390x?
No, for the same reasons it doesn't exist in MVS. Paul is suggesting that -m32 be created. He can make his arguments to the Linux community in the Linux kernel mailing list (LKML), but I think they will throw cold water on it. As Dave Rivers rightly points out, the machine simply will not deliver 32-bit semantics, and trying to get various system interfaces to fake it wastes your time and annoys the pig. While Paul doesn't need to express the value of AM32 (it's obvious), he hasn't been able to express the value of hamstringing an AM64 application to pretend to be AM32. IMO, if an application needs more than 2GB memory, then simply doubling the memory is a delaying tactic of dubious value. It's obviously growing and will soon need more than 4GB. Alan Altmark Senior Managing z/VM and Linux Consultant IBM Systems Lab Services IBM Z Delivery Practice ibm.com/systems/services/labservices office: 607.429.3323 mobile; 607.321.7556 [email protected] IBM Endicott ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
