On 07.12.2016 07:51, Martin Kletzander wrote: > On Tue, Dec 06, 2016 at 01:03:29PM +0100, Viktor Mihajlovski > wrote: >> With kernel 3.18 (since commit >> 3e32cb2e0a12b6915056ff04601cf1bb9b44f967) the "unlimited" value >> for cgroup memory limits has changed once again as its byte value >> is now computed from a page counter. The new "unlimited" value >> reported by the cgroup fs is therefore 2**51-1 pages which is >> (VIR_DOMAIN_MEMORY_PARAM_UNLIMITED - 3072). This results e.g. in >> virsh memtune displaying 9007199254740988 instead of unlimited >> for the limits. >> >> This patch uses the value of memory.limit_in_bytes from the >> cgroup memory root which is the system's "real" unlimited value >> for comparison. >> >> See also libvirt commit 231656bbeb9e4d3bedc44362784c35eee21cf0f4 >> for the history for kernel 3.12 and before. >> >> Signed-off-by: Viktor Mihajlovski <mihajlov@xxxxxxxxxxxxxxxxxx> >> --- >> >> v2: - removed RFC verbiage from commit message - per Martin's >> review comment, cache the cgroup memory.limit_in_bytes - used the >> cgroup detection logic proposed by Martin, much nicer now indeed >> - other than initially planned, fall back to >> VIR_DOMAIN_MEMORY_PARAM_UNLIMITED in case of cgroup read failure, >> since the usual paranoia fits in nicely with the "already >> initialized" check. With the current code structure this will >> never be called when the memory controller is not configured or >> mounted anyway... - while at it, replaced the goto cleanups with >> direct returns as there's really no cleanup to be done in the >> GetMemoryxxxLimit functions >> >> v3: - use thread safe one time initialization for the "unlimited" >> value, to account for 64-bit architectures which do not guarantee >> atomic memory updates of long long values (which reportedly is >> the case for ARM). >> > > Perfect, ACK, pushed, thanks. Great. Thanks! -- Mit freundlichen Grüßen/Kind Regards Viktor Mihajlovski IBM Deutschland Research & Development GmbH Vorsitzender des Aufsichtsrats: Martina Köderitz Geschäftsführung: Dirk Wittkopp Sitz der Gesellschaft: Böblingen Registergericht: Amtsgericht Stuttgart, HRB 243294 -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list
