From 4597eca1415668dcb6a99f0321b845c125ae4670 Mon Sep 17 00:00:00 2001
From: usiegl00 <50933431+usiegl00@users.noreply.github.com>
Date: Sun, 21 Jan 2024 10:58:13 +0900
Subject: [PATCH 1/2] cgroup support for physical_processor_count

---
 .../concurrent/utility/processor_counter.rb   | 22 +++++++++++--------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/lib/concurrent-ruby/concurrent/utility/processor_counter.rb b/lib/concurrent-ruby/concurrent/utility/processor_counter.rb
index 986e2d523..b90d818df 100644
--- a/lib/concurrent-ruby/concurrent/utility/processor_counter.rb
+++ b/lib/concurrent-ruby/concurrent/utility/processor_counter.rb
@@ -36,17 +36,21 @@ def compute_physical_processor_count
               when /darwin\d\d/
                 IO.popen("/usr/sbin/sysctl -n hw.physicalcpu", &:read).to_i
               when /linux/
-                cores = {} # unique physical ID / core ID combinations
-                phy   = 0
-                IO.read("/proc/cpuinfo").scan(/^physical id.*|^core id.*/) do |ln|
-                  if ln.start_with?("physical")
-                    phy = ln[/\d+/]
-                  elsif ln.start_with?("core")
-                    cid        = phy + ":" + ln[/\d+/]
-                    cores[cid] = true if not cores[cid]
+                if Dir.exist?("/sys/fs/cgroup/cpu,cpuacct") && (cfs_quota_us = IO.read("/sys/fs/cgroup/cpu,cpuacct/cpu.cfs_quota_us").to_i) > 0
+                  (cfs_quota_us / IO.read("/sys/fs/cgroup/cpu,cpuacct/cpu.cfs_period_us").to_i.to_f).ceil
+                else
+                  cores = {} # unique physical ID / core ID combinations
+                  phy   = 0
+                  IO.read("/proc/cpuinfo").scan(/^physical id.*|^core id.*/) do |ln|
+                    if ln.start_with?("physical")
+                      phy = ln[/\d+/]
+                    elsif ln.start_with?("core")
+                      cid        = phy + ":" + ln[/\d+/]
+                      cores[cid] = true if not cores[cid]
+                    end
                   end
+                  cores.count
                 end
-                cores.count
               when /mswin|mingw/
                 require 'win32ole'
                 result_set = WIN32OLE.connect("winmgmts://").ExecQuery(

From 5296b55e9b05ebbdc9da27d6f8b1f7c51a2b2bbe Mon Sep 17 00:00:00 2001
From: usiegl00 <50933431+usiegl00@users.noreply.github.com>
Date: Tue, 23 Jan 2024 09:06:20 +0900
Subject: [PATCH 2/2] add reference link for cgroup support for
 physical_processor_count

---
 lib/concurrent-ruby/concurrent/utility/processor_counter.rb | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/concurrent-ruby/concurrent/utility/processor_counter.rb b/lib/concurrent-ruby/concurrent/utility/processor_counter.rb
index b90d818df..57b10fdcb 100644
--- a/lib/concurrent-ruby/concurrent/utility/processor_counter.rb
+++ b/lib/concurrent-ruby/concurrent/utility/processor_counter.rb
@@ -36,8 +36,9 @@ def compute_physical_processor_count
               when /darwin\d\d/
                 IO.popen("/usr/sbin/sysctl -n hw.physicalcpu", &:read).to_i
               when /linux/
-                if Dir.exist?("/sys/fs/cgroup/cpu,cpuacct") && (cfs_quota_us = IO.read("/sys/fs/cgroup/cpu,cpuacct/cpu.cfs_quota_us").to_i) > 0
-                  (cfs_quota_us / IO.read("/sys/fs/cgroup/cpu,cpuacct/cpu.cfs_period_us").to_i.to_f).ceil
+                # https://kernel.googlesource.com/pub/scm/linux/kernel/git/glommer/memcg/+/cpu_stat/Documentation/cgroups/cpu.txt
+                if Dir.exist?("/sys/fs/cgroup/cpu,cpuacct") && (cfs_quota_us = File.read("/sys/fs/cgroup/cpu,cpuacct/cpu.cfs_quota_us").to_i) > 0
+                  (cfs_quota_us / File.read("/sys/fs/cgroup/cpu,cpuacct/cpu.cfs_period_us").to_f).ceil
                 else
                   cores = {} # unique physical ID / core ID combinations
                   phy   = 0