Incorrect data for Apple Silicon, needs bump to 2.8.0

[plessl]

I was trying to query the cache sizes using hwloc on a Mac with an Apple Silcon (M1) processor. The currently used version of 2.7.1 hwloc returns faulty data or throws errors. For example, cachesize() fails:

julia> cachesize()
ERROR: BoundsError: attempt to access 0-element Vector{Any} at index [1]
Stacktrace:
 [1] getindex
   @ ./array.jl:924 [inlined]
 [2] first(a::Vector{Any})
   @ Base ./abstractarray.jl:404
 [3] cachesize()
   @ Hwloc ~/.julia/packages/Hwloc/HorQV/src/highlevel_api.jl:205
 [4] top-level scope
   @ REPL[5]:1

and topology yields incorrect data (performance and efficiency cores appear to have same cache size, which is not correct.

julia> topology()
Machine (3.26 GB)
    Package L#0 P#0 (3.26 GB)
        NUMANode (3.26 GB)
        L2 (4.0 MB)
            L1 (64.0 kB) + Core L#0 P#0 
                PU L#0 P#0 
            L1 (64.0 kB) + Core L#1 P#1 
                PU L#1 P#1 
            L1 (64.0 kB) + Core L#2 P#2 
                PU L#2 P#2 
            L1 (64.0 kB) + Core L#3 P#3 
                PU L#3 P#3 
        L2 (4.0 MB)
            L1 (64.0 kB) + Core L#4 P#4 
                PU L#4 P#4 
            L1 (64.0 kB) + Core L#5 P#5 
                PU L#5 P#5 
            L1 (64.0 kB) + Core L#6 P#6 
                PU L#6 P#6 
            L1 (64.0 kB) + Core L#7 P#7 
                PU L#7 P#7 

The most recent release 2.8.0 of hwloc does now officially support M1 processors (https://www.mail-archive.com/[email protected]/msg00151.html) and the output of lstopo looks sane:

lstopo
Machine (3337MB total)
  Package L#0
    NUMANode L#0 (P#0 3337MB)
    L2 L#0 (4096KB)
      L1d L#0 (64KB) + L1i L#0 (128KB) + Core L#0 + PU L#0 (P#0)
      L1d L#1 (64KB) + L1i L#1 (128KB) + Core L#1 + PU L#1 (P#1)
      L1d L#2 (64KB) + L1i L#2 (128KB) + Core L#2 + PU L#2 (P#2)
      L1d L#3 (64KB) + L1i L#3 (128KB) + Core L#3 + PU L#3 (P#3)
    L2 L#1 (12MB)
      L1d L#4 (128KB) + L1i L#4 (192KB) + Core L#4 + PU L#4 (P#4)
      L1d L#5 (128KB) + L1i L#5 (192KB) + Core L#5 + PU L#5 (P#5)
      L1d L#6 (128KB) + L1i L#6 (192KB) + Core L#6 + PU L#6 (P#6)
      L1d L#7 (128KB) + L1i L#7 (192KB) + Core L#7 + PU L#7 (P#7)
  CoProc(OpenCL) "opencl0d0"

Since Hwloc.jl is the most convenient tool to access CPU architecture information in a cross-CPU manner, it would be great if you would bump the bundled version of hwloc to the latest version.

Cheers
Christian

[eschnett]

@plessl The respective update is waiting for review: JuliaPackaging/Yggdrasil#5300

[carstenbauer]

There will soon be a new version of Hwloc_jll. The corresponding pipelines are running: https://dev.azure.com/JuliaPackaging/Yggdrasil/_build/results?buildId=21337&view=results

[carstenbauer]

If you ] up Hwloc you should get the new version of Hwloc_jll (2.8.0). On an M1, this will give you:

julia> topology()
Machine (3.49 GB)
    Package L#0 P#0 (3.49 GB)
        NUMANode (3.49 GB)
        L2 (4.0 MB)
            L1 (64.0 kB) + I1Cache Cache{size=131072,depth=1,linesize=128,associativity=0,type=Instruction}
                Core L#0 P#0
                    PU L#0 P#0
            L1 (64.0 kB) + I1Cache Cache{size=131072,depth=1,linesize=128,associativity=0,type=Instruction}
                Core L#1 P#1
                    PU L#1 P#1
            L1 (64.0 kB) + I1Cache Cache{size=131072,depth=1,linesize=128,associativity=0,type=Instruction}
                Core L#2 P#2
                    PU L#2 P#2
            L1 (64.0 kB) + I1Cache Cache{size=131072,depth=1,linesize=128,associativity=0,type=Instruction}
                Core L#3 P#3
                    PU L#3 P#3
        L2 (12.0 MB)
            L1 (128.0 kB) + I1Cache Cache{size=196608,depth=1,linesize=128,associativity=0,type=Instruction}
                Core L#4 P#4
                    PU L#4 P#4
            L1 (128.0 kB) + I1Cache Cache{size=196608,depth=1,linesize=128,associativity=0,type=Instruction}
                Core L#5 P#5
                    PU L#5 P#5
            L1 (128.0 kB) + I1Cache Cache{size=196608,depth=1,linesize=128,associativity=0,type=Instruction}
                Core L#6 P#6
                    PU L#6 P#6
            L1 (128.0 kB) + I1Cache Cache{size=196608,depth=1,linesize=128,associativity=0,type=Instruction}
                Core L#7 P#7
                    PU L#7 P#7
julia> Hwloc.l1cache_sizes()
8-element Vector{Int64}:
  65536
  65536
  65536
  65536
 131072
 131072
 131072
 131072

julia> Hwloc.l2cache_sizes()
2-element Vector{Int64}:
  4194304
 12582912

The printing of the I1Cache elements in the topology() output could be improved but the information should be correct now. Note that you can't use cachesize() because not all caches of the same kind have the same size.

(Closing this for now. Feel free to reopen if necessary.)

[plessl]

Using Hwloc.l1cache_sizes() and Hwloc.l2cache_sizes() works for my current use case.

However, cachesize() and cachelinesize() fail now with BoundsError. I think this should be considered as bug.

Shall I go ahead open another issue?

[carstenbauer]

I took care of it and created #59 (and #60 for the formatting improvements). I think I'll be able to fix it later today.