On Apr 11 09:02, Corinna Vinschen wrote:
> THanks for the report but this belongs to the cygwin ML.
> I'm redirecting this here.
>
>
> Corinna
>
> On Apr 10 18:36, Achim Gratz wrote:
> >
> > As briefly discussed on IRC I've got a new Server 2016 blade with 2
> > sockets × 8 cores × 2 HT =32 logical processors and Cygwin spews errors
> > for processor ID 16 and up (also top doesn't quite work, which likely
> > has the same reason, although the code path may be unrelated to the
> > /proc/cpuinfo bug described here).
> >
> > --8<---------------cut here---------------start------------->8---
> > 64bit (166)~ > cat /proc/cpuinfo
> > 0 [main] cat 10068 format_proc_cpuinfo:
> > SetThreadGroupAffinity(10000,0 (10/16)) failed Win32 error 87
> > [...]
> > This results in Windows coming up with two 64 core processor groups that
> > have 16 active logical processors each:
> >
> > --8<---------------cut here---------------start------------->8---
> > (gdb) print plpi
> > $1 = (PSYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX) 0x600008020
> > (gdb) print *plpi
> > $2 = {Relationship = RelationGroup, Size = 128, {Processor = {Flags = 2
> > '\002', Reserved = "\000\002", '\000' <repeats 18 times>, GroupCount = 0,
> > GroupMask = {{Mask = 4160, Group = 0, Reserved = {0, 0, 0}}}},
> > NumaNode = {NodeNumber = 131074, Reserved = '\000' <repeats 19 times>,
> > GroupMask = {Mask = 4160, Group = 0, Reserved = {0, 0, 0}}}, Cache =
> > {Level = 2 '\002', Associativity = 0 '\000', LineSize = 2, CacheSize = 0,
> > Type = CacheUnified, Reserved = '\000' <repeats 12 times>,
> > "@\020\000\000\000\000\000", GroupMask = {Mask = 0, Group = 0, Reserved =
> > {0, 0,
> > 0}}}, Group = {MaximumGroupCount = 2, ActiveGroupCount = 2,
> > Reserved = '\000' <repeats 19 times>, GroupInfo = {{
> > MaximumProcessorCount = 64 '@', ActiveProcessorCount = 16 '\020',
> > Reserved = '\000' <repeats 37 times>, ActiveProcessorMask = 65535}}}}}
> > --8<---------------cut here---------------end--------------->8---
> >
> > I've confirmed that the error message is not printed if I manually
> > correct the information for processor ID 17 as follows:
> > [...]I'm a bit puzzled about the connection between MaximumProcessorCount and ActiveProcessorCount here. Why isn't MaximumProcessorCount 16 as well? Setting it to 64 doesn't make any sense for a system with 32 logical CPUs in total. I'm not sure just simply using ActiveProcessorCount rather than MaximumProcessorCount is the right thing to do... > > As an aside, the cache size is reported as 256kiB (not just for this > > processor, but also for a Celeron 1037U on another machine), which seems > > to be the L2 cache for a single hardware core on these architectures. > > Linux now reports L3 cache sizes (and possibly L4 if present) for these > > (20MiB and 2MiB per socket respectively). L3 is easy. Checking the Linux kernel source I don't see that it reports L4. Corinna -- Corinna Vinschen Please, send mails regarding Cygwin to Cygwin Maintainer cygwin AT cygwin DOT com Red Hat
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