On Thursday, 07/09/2015 at 01:16 EDT, Michael MacIsaac <mike99...@gmail.com> wrote: > I'm going to stop here for now. I've learned a lot about Linux memory from > this thread (but that's easy when you don't know much to begin with :)). > > I guess a question to the Linux developers in Germany would be: > > If vmcp is called with a buffer of 1M and the last slab in /proc/buddyinfo > is 0, would it not be reasonable to nudge the kernel to free at least one > slot up, assuming this can be done safely?
My 0.02 USD: CP has similar issues for I/O and V-SIE. Slab creation (coalescing adjacent page frames into larger slabs) is a function that is intended to ensure the available count for each slab is > 0. The ideal time to create a larger slab is when memory is being released. The only way to get larger slabs is to force more memory to be released. This is why the cache controls discussed here are important - they keep as much memory released as advisable. So there's no point in nudging the kernel to do a Hail Mary attempt to find more memory. If it were available, the slab count would already be > 0. Alan Altmark Senior Managing z/VM and Linux Consultant Lab Services System z Delivery Practice IBM Systems & Technology Group ibm.com/systems/services/labservices office: 607.429.3323 mobile; 607.321.7556 alan_altm...@us.ibm.com IBM Endicott ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu 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/
