SPL: Memory Allocator improvements

[haer22]

Does line in the Changelog: "SPL: Memory Allocator improvements (Sean Doran)" imply that the memory handling is smoother now? No more freezes?

[lundman]

We would like to believe we have solved most stutter problems with this version. There are 2 more commits after the release for a special case involving VMs.

[zenomt]

i noticed after installing 1.6.1 on my Mavericks system that VirtualBox stopped working (the VBoxDrv kext aborts its startup when it tries to allocate some memory in "the first 4GB"). i ended up going back to 1.5.2 for now.

is the "special case involving VMs" expected to address this case?

[Brendon]

I just installed virtualbox, and installed linux in a VM without issue. This is on a 2013 MacPro with 32GB of RAM. VM was stored on ZFS.

Could you please provide more details as to what you are experiencing.

- Brendon

[zenomt]

on a 2013 Mac Pro with 64GB of RAM, running Mac OS X 10.9.5 Mavericks. with O3X 1.6.1 installed and filesystems mounted (i didn't try with the ZFS drivers loaded but no pools imported), the VBoxDrv.kext (5.1.14 r112924 plus several earlier releases) wouldn't load. it printed out

supdrvGipCreate: failed to allocate the GIP page. rc=-71

-71 is VERR_MEMOBJ_INIT_FAILED. this error occurs in VirtualBox src/VBox/HostDrivers/Support/SUPDrvGip.cpp line 1881 of the 5.1.14 source tarball, after RTR0MemObjAllocCont() returns VERR_MEMOBJ_INIT_FAILED. RTR0MemObjAllocCont() is trying to allocate in the first 4GB of address space (presumably of physical memory in the kernel context). i don't believe it's trying to allocate all that much.

i tried repeatedly uninstalling and reinstalling VBox, including different versions, and also uninstalling/reinstalling O3X 1.6.1. the problem persisted. VBox loaded correctly after reverting to O3X 1.5.2.

i was curious what the "special case involving VMs" in lundman's post was referring to, and if it might be relevant for my situation. if nobody else is seeing this problem in later versions of Mac OS X, perhaps this is the push i need to upgrade. Mavericks is starting to get pretty stale. according to the O3X build-from-source instructions, it's too old (latest available Xcode for Mavericks is 6.2, 6.3+ is required to build).

[Brendon]

The "special case" is nothing to do with Virtualbox unfortunately. Just the continued war against memory fragmentation under certain conditions with all ZFS implementations.

- Brendon