$yum install mdadm -y
$git clone git://neil.brown.name/mdadm

$dd if=/dev/zero of=disk1.img bs=512 count=4096000
$losetup /dev/loop2 disk1.img
...

mdadm --create --verbose /dev/md0 --level=stripe --raid-devices=2 /dev/loop2 /dev/loop3
mdadm --manage --stop /dev/md0

$fdisk -l
...
Disk /dev/md0: 4192 MB, 4192206848 bytes, 8187904 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 524288 bytes / 1048576 bytes

$lsblk
NAME  MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
...
loop2  7:2    0     2G  0 loop  
└─md0  9:0    0   3.9G  0 raid0 
loop3  7:3    0     2G  0 loop  
└─md0  9:0    0   3.9G  0 raid0

// 创建4设备组成的raid0设备，16384000是4个设备总的Sector数量， 0 是每个设备的偏移量
$dmsetup create test-raid0 --table '0 16384000 striped 4 128 /dev/loop4 0 /dev/loop5 0 /dev/loop6 0 /dev/loop7 0'

$lsblk
loop4         7:4    0     2G  0 loop  
└─test-raid0  253:23   0   7.8G  0 dm    
loop5         7:5    0     2G  0 loop  
└─test-raid0  53:23   0   7.8G  0 dm    
loop6         7:6    0     2G  0 loop  
└─test-raid0  253:23   0   7.8G  0 dm    
loop7         7:7    0     2G  0 loop  
└─test-raid0  253:23   0   7.8G  0 dm

$fdisk -l
...
Disk /dev/mapper/test-raid0: 8388 MB, 8388608000 bytes, 16384000 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 65536 bytes / 262144 bytes

$dmsetup status test-raid0
0 16384000 striped 4 7:4 7:5 7:6 7:7 1 AAAA

$mdadm --create --verbose /dev/md0 --level=mirror --raid-devices=2 /dev/loop2 /dev/loop3

// 4096000是单个设备的sector数量，因为mirror没有扩大容量，2是设备数量， - 表示没有metadata 设备
$dmsetup create test-raid1 --table '0 4096000 raid raid1 3 0 region_size 1024 2 - /dev/loop4 - /dev/loop5'
//下面的是有metadata设备的raid1创建
$dmsetup create test-raid1 --table '0 4096000 raid raid1 3 0 region_size 1024 2 /dev/loop4 /dev/loop5 /dev/loop6 /dev/loop7'

$dmsetup status test-raid1
0 4096000 raid raid1 2 AA 4096000/4096000 idle 0

// spare device指定备用磁盘，创建3块盘的RAID5
$mdadm --create --verbose /dev/md1 --level=5 --raid-devices=3 /dev/loop4 /dev/loop5 /dev/loop6 --spare-devices=1 /dev/loop7

`$mdadm --detail /dev/md1/dev/md1:        Version : 1.2  Creation Time : Tue Mar  7 16:57:39 2017     Raid Level : raid5     Array Size : 4093952 (3.90 GiB 4.19 GB)  Used Dev Size : 2046976 (1999.34 MiB 2096.10 MB)   Raid Devices : 3  Total Devices : 4    Persistence : Superblock is persistent    Update Time : Tue Mar  7 16:57:57 2017          State : clean  Active Devices : 3Working Devices : 4 Failed Devices : 0  Spare Devices : 1         Layout : left-symmetric     Chunk Size : 512K           Name : st-integrat-node00:1  (local to host st-integrat-node00)           UUID : 071d2e75:2029e9a2:2e427dd9:d2ab804f         Events : 18    Number   Major   Minor   RaidDevice State       0       7        4        0      active sync   /dev/loop4       1       7        5        1      active sync   /dev/loop5       4       7        6        2      active sync   /dev/loop6       3       7        7        -      spare   /dev/loop7`

// 这里创建了没有metadata设备的4个设备的raid5，因此大小是3倍磁盘扇区大小，有一个作为奇偶校验。 
$dmsetup create test-raid5 --table '0 12288000 raid raid5_ls 3 64 region_size 1024 4 - /dev/loop4 - /dev/loop5 - /dev/loop6 - /dev/loop7'
// metadata设备的创建过程和前面RAID1的类似，这里略过。
//devicemapper还可以创建degraded RAID5,只需将最后一个设备置为 - 即可。
$dmsetup create test-raid5 --table '0 12288000 raid raid5_ls 3 64 region_size 1024 4 - /dev/loop4 - /dev/loop5 - - -

$mdadm --create --verbose /dev/md1 --level=10 --raid-devices=4 /dev/loop4 /dev/loop5 /dev/loop6 /dev/loop7
mdadm: layout defaults to n2
mdadm: layout defaults to n2
mdadm: chunk size defaults to 512K
mdadm: size set to 2046976K
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md1 started.

$mdadm --detail /dev/md1
/dev/md1:
        Version : 1.2
  Creation Time : Tue Mar  7 17:44:43 2017
     Raid Level : raid10
     Array Size : 4093952 (3.90 GiB 4.19 GB)
  Used Dev Size : 2046976 (1999.34 MiB 2096.10 MB)
   Raid Devices : 4
  Total Devices : 4
    Persistence : Superblock is persistent

    Update Time : Tue Mar  7 17:45:04 2017
          State : clean 
 Active Devices : 4
Working Devices : 4
 Failed Devices : 0
  Spare Devices : 0

         Layout : near=2
     Chunk Size : 512K

           Name : st-integrat-node00:1  (local to host st-integrat-node00)
           UUID : 643b371a:eeadc82d:7d4effee:cf00411c
         Events : 17

    Number   Major   Minor   RaidDevice State
       0       7        4        0      active sync set-A   /dev/loop4
       1       7        5        1      active sync set-B   /dev/loop5
       2       7        6        2      active sync set-A   /dev/loop6
       3       7        7        3      active sync set-B   /dev/loop7

// 创建4个drive的RAID10，一半做镜像，所以大小为2倍drive sector大小。
$dmsetup create test-raid10 --table '0 8192000 raid raid10 3 64 region_size 1024 4 - /dev/loop4 - /dev/loop5 - /dev/loop6 - /dev/loop7'

$dmsetup status test-raid10
0 8192000 raid raid10 4 AAAA 8192000/8192000 idle 0

func Next(str string) []int {
    length := len(str)
    next := make([]int, length) // next数组
    for q := 1; q < length; q++ {
        m := 0
        for k := 0; k < q; k++ {
            if str[:k+1] == str[q-k:q+1] && k+1 > m{ //如果前缀等于后缀, 并且长度是最长的, 就替换m
                m = k+1
            }
        }
        next[q] = m // m是写入next数组, 循环q
    }
    return next
}

func Next(str string) []int {
    length := len(str)
    next := make([]int, length)
    next[0] = 0 // 初始化为0, 表示没有
    for q := 1; q < length; q++ {
        k := next[q - 1] // 只需要退回到前一个的next[q-1]位置, 而不用回到0
        for k > 0 && str[k] != str[q] { // 如果后一个位置不相等, 再往前回溯
            k = next[k] // 为什么这里不直接跳回到0呢, 因为next[k]表示前面已经匹配的, 而不需要退到起点, 先从最大长度往前回溯
        }
        if str[k] == str[q] {
            // 如果下一个字符相等, 将将k + 1, 由于前面的字串肯定是相等的, 不需要在比较
            next[q] = k + 1
        } else {
            next[q] = 0 // 如果不相等
        }
    }
    return next
}

func kmp(str1, str2 string) bool {
    next := Next(str2)
    i := 0 // i 是str1的index
    j := 0 // j 是str2的index
    length := len(str1)
    for i < length {
        if str1[i+j] == str2[j] {
            j++
            if j == len(str2) {
                // 完全匹配
                return true
            }
            continue
        }
        if j == 0 { // j==0 字节i++ 跳过
            i++
        } else {
            i = i + j - next[j-1]//移动位数 = 已匹配的字符数 - 对应的部分匹配值
            j = next[j - 1] // j回溯到记录位置
        }
    }
    return false
}

func main() {
    str1 := "BBC ABCDAB ABCDABCDABDE"
    str := "ABCDABD"
    fmt.Println(kmp(str1, str))
}

Sending build context to Docker daemon   220 MB
Step 1 : FROM warpdrive:tos-release-1-5
 ---> 769306738d96
Step 2 : COPY . /go/src/github.com/transwarp/warpdrive/
 ---> 07c99697b16e
Removing intermediate container 127c0e71a84b
Successfully built 07c99697b16e
/usr/bin/docker: Error response from daemon: invalid header field value "oci runtime error: container_linux.go:247: starting container process caused \"process_linux.go:245: running exec setns process for init caused \\\"exit status 6\\\"\"\n".
FATA[0301] exit status 125                              
make: *** [build] Error 1

#从这里的输出可以看到，cpuset被挂载在了/sys/fs/cgroup/cpuset，
#而cpu和cpuacct一起挂载到了/sys/fs/cgroup/cpu,cpuacct下面
dev@ubuntu:~$ mount|grep cpu
cgroup on /sys/fs/cgroup/cpuset type cgroup (rw,nosuid,nodev,noexec,relatime,cpuset)
cgroup on /sys/fs/cgroup/cpu,cpuacct type cgroup (rw,nosuid,nodev,noexec,relatime,cpu,cpuacct)

#进入/sys/fs/cgroup/cpu,cpuacct并创建子cgroup
dev@ubuntu:~$ cd /sys/fs/cgroup/cpu,cpuacct
dev@ubuntu:/sys/fs/cgroup/cpu,cpuacct$ sudo mkdir test
dev@ubuntu:/sys/fs/cgroup/cpu,cpuacct$ cd test
dev@ubuntu:/sys/fs/cgroup/cpu,cpuacct/test$ ls
cgroup.clone_children  cpuacct.stat   cpuacct.usage_percpu  cpu.cfs_quota_us  cpu.stat           tasks
cgroup.procs           cpuacct.usage  cpu.cfs_period_us     cpu.shares        notify_on_release

1.限制只能使用1个CPU（每250ms能使用250ms的CPU时间）
    # echo 250000 > cpu.cfs_quota_us /* quota = 250ms */
    # echo 250000 > cpu.cfs_period_us /* period = 250ms */

2.限制使用2个CPU（内核）（每500ms能使用1000ms的CPU时间，即使用两个内核）
    # echo 1000000 > cpu.cfs_quota_us /* quota = 1000ms */
    # echo 500000 > cpu.cfs_period_us /* period = 500ms */

3.限制使用1个CPU的20%（每50ms能使用10ms的CPU时间，即使用一个CPU核心的20%）
    # echo 10000 > cpu.cfs_quota_us /* quota = 10ms */
    # echo 50000 > cpu.cfs_period_us /* period = 50ms */

#继续使用上面创建的子cgroup： test
#设置只能使用1个cpu的20%的时间
dev@ubuntu:/sys/fs/cgroup/cpu,cpuacct/test$ sudo sh -c "echo 50000 > cpu.cfs_period_us"
dev@ubuntu:/sys/fs/cgroup/cpu,cpuacct/test$ sudo sh -c "echo 10000 > cpu.cfs_quota_us"

#将当前bash加入到该cgroup
dev@ubuntu:/sys/fs/cgroup/cpu,cpuacct/test$ echo $$
5456
dev@ubuntu:/sys/fs/cgroup/cpu,cpuacct/test$ sudo sh -c "echo 5456 > cgroup.procs"

#在bash中启动一个死循环来消耗cpu，正常情况下应该使用100%的cpu（即消耗一个内核）
dev@ubuntu:/sys/fs/cgroup/cpu,cpuacct/test$ while :; do echo test > /dev/null; done

#--------------------------重新打开一个shell窗口----------------------
#通过top命令可以看到5456的CPU使用率为20%左右，说明被限制住了
#不过这时系统的%us+%sy在10%左右，那是因为我测试的机器上cpu是双核的，
#所以系统整体的cpu使用率为10%左右
dev@ubuntu:~$ top
Tasks: 139 total,   2 running, 137 sleeping,   0 stopped,   0 zombie
%Cpu(s):  5.6 us,  6.2 sy,  0.0 ni, 88.2 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st
KiB Mem :   499984 total,    15472 free,    81488 used,   403024 buff/cache
KiB Swap:        0 total,        0 free,        0 used.   383332 avail Mem

  PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMAND
 5456 dev       20   0   22640   5472   3524 R  20.3  1.1   0:04.62 bash

#这时可以看到被限制的统计结果
dev@ubuntu:~$ cat /sys/fs/cgroup/cpu,cpuacct/test/cpu.stat
nr_periods 1436
nr_throttled 1304
throttled_time 51542291833

func (s *MemoryGroup) Set(path string, cgroup *configs.Cgroup) error {
	if err := setMemoryAndSwap(path, cgroup); err != nil {
		return err
	}

	if cgroup.Resources.KernelMemory != 0 {
		if err := setKernelMemory(path, cgroup.Resources.KernelMemory); err != nil {
			return err
		}
	}

	if cgroup.Resources.MemoryReservation != 0 {
		if err := writeFile(path, "memory.soft_limit_in_bytes", strconv.FormatInt(cgroup.Resources.MemoryReservation, 10)); err != nil {
			return err
		}
	}

	if cgroup.Resources.KernelMemoryTCP != 0 {
		if err := writeFile(path, "memory.kmem.tcp.limit_in_bytes", strconv.FormatInt(cgroup.Resources.KernelMemoryTCP, 10)); err != nil {
			return err
		}
	}
	if cgroup.Resources.OomKillDisable {
		if err := writeFile(path, "memory.oom_control", "1"); err != nil {
			return err
		}
	}
	if cgroup.Resources.MemorySwappiness == nil || int64(*cgroup.Resources.MemorySwappiness) == -1 {
		return nil
	} else if *cgroup.Resources.MemorySwappiness <= 100 {
		if err := writeFile(path, "memory.swappiness", strconv.FormatUint(*cgroup.Resources.MemorySwappiness, 10)); err != nil {
			return err
		}
	} else {
		return fmt.Errorf("invalid value:%d. valid memory swappiness range is 0-100", *cgroup.Resources.MemorySwappiness)
	}

	return nil
}

func (s *MemoryGroup) Apply(d *cgroupData) (err error) {
	path, err := d.path("memory")
	if err != nil && !cgroups.IsNotFound(err) {
		return err
	} else if path == "" {
		return nil
	}
	if memoryAssigned(d.config) {
		if _, err := os.Stat(path); os.IsNotExist(err) {
			if err := os.MkdirAll(path, 0755); err != nil {
				return err
			}
			// 只有内核内存可以动态设置
			if err := EnableKernelMemoryAccounting(path); err != nil {
				return err
			}
		}
	}
	...
}

func EnableKernelMemoryAccounting(path string) error {
	// Check if kernel memory is enabled
	// We have to limit the kernel memory here as it won't be accounted at all
	// until a limit is set on the cgroup and limit cannot be set once the
	// cgroup has children, or if there are already tasks in the cgroup.
	for _, i := range []int64{1, -1} {
		if err := setKernelMemory(path, i); err != nil {
			return err
		}
	}
	return nil
}

func (s *CpuGroup) Set(path string, cgroup *configs.Cgroup) error {
    // 设置CFS 
	if cgroup.Resources.CpuShares != 0 {
		if err := writeFile(path, "cpu.shares", strconv.FormatUint(cgroup.Resources.CpuShares, 10)); err != nil {
			return err
		}
	}
	if cgroup.Resources.CpuPeriod != 0 {
		if err := writeFile(path, "cpu.cfs_period_us", strconv.FormatUint(cgroup.Resources.CpuPeriod, 10)); err != nil {
			return err
		}
	}
	if cgroup.Resources.CpuQuota != 0 {
		if err := writeFile(path, "cpu.cfs_quota_us", strconv.FormatInt(cgroup.Resources.CpuQuota, 10)); err != nil {
			return err
		}
	}
	// 设置RT
	if err := s.SetRtSched(path, cgroup); err != nil {
		return err
	}

	return nil
}

func (s *CpuGroup) SetRtSched(path string, cgroup *configs.Cgroup) error {
	if cgroup.Resources.CpuRtPeriod != 0 {
		if err := writeFile(path, "cpu.rt_period_us", strconv.FormatUint(cgroup.Resources.CpuRtPeriod, 10)); err != nil {
			return err
		}
	}
	if cgroup.Resources.CpuRtRuntime != 0 {
		if err := writeFile(path, "cpu.rt_runtime_us", strconv.FormatInt(cgroup.Resources.CpuRtRuntime, 10)); err != nil {
			return err
		}
	}
	return nil
}

func (s *CpuGroup) Apply(d *cgroupData) error {
	// We always want to join the cpu group, to allow fair cpu scheduling
	// on a container basis
	path, err := d.path("cpu")
	if err != nil && !cgroups.IsNotFound(err) {
		return err
	}
	return s.ApplyDir(path, d.config, d.pid)
}

func (s *CpuGroup) ApplyDir(path string, cgroup *configs.Cgroup, pid int) error {
	// This might happen if we have no cpu cgroup mounted.
	// Just do nothing and don't fail.
	if path == "" {
		return nil
	}
	if err := os.MkdirAll(path, 0755); err != nil {
		return err
	}
	// We should set the real-Time group scheduling settings before moving
	// in the process because if the process is already in SCHED_RR mode
	// and no RT bandwidth is set, adding it will fail.
	if err := s.SetRtSched(path, cgroup); err != nil {
		return err
	}
	// because we are not using d.join we need to place the pid into the procs file
	// unlike the other subsystems
	if err := cgroups.WriteCgroupProc(path, pid); err != nil {
		return err
	}

	return nil
}

// cgroupManagerImpl implements the CgroupManager interface.
// Its a stateless object which can be used to
// update,create or delete any number of cgroups
// It uses the Libcontainer raw fs cgroup manager for cgroup management.
type cgroupManagerImpl struct {
	// subsystems holds information about all the
	// mounted cgroup subsystems on the node
	subsystems *CgroupSubsystems
	// simplifies interaction with libcontainer and its cgroup managers
	adapter *libcontainerAdapter
}

// Update updates the cgroup with the specified Cgroup Configuration
func (m *cgroupManagerImpl) Update(cgroupConfig *CgroupConfig) error {
	...
	// 提取cgroup资源参数
	resourceConfig := cgroupConfig.ResourceParameters
	resources := m.toResources(resourceConfig)

	cgroupPaths := m.buildCgroupPaths(cgroupConfig.Name)

	// 获得cgroupfs的位置.
	abstractCgroupFsName := string(cgroupConfig.Name)
	abstractParent := CgroupName(path.Dir(abstractCgroupFsName))
	abstractName := CgroupName(path.Base(abstractCgroupFsName))

	driverParent := m.adapter.adaptName(abstractParent, false)
	driverName := m.adapter.adaptName(abstractName, false)

	// 获取systemd的绝对位置
	if m.adapter.cgroupManagerType == libcontainerSystemd {
		driverName = m.adapter.adaptName(cgroupConfig.Name, false)
	}

	// 初始化cgroup配置
	libcontainerCgroupConfig := &libcontainerconfigs.Cgroup{
		Name:      driverName,
		Parent:    driverParent,
		Resources: resources,
		Paths:     cgroupPaths,
	}

    // 设置cgroup配置
	if err := setSupportedSubsystems(libcontainerCgroupConfig); err != nil {
		return fmt.Errorf("failed to set supported cgroup subsystems for cgroup %v: %v", cgroupConfig.Name, err)
	}
	return nil
}

func (m *cgroupManagerImpl) toResources(resourceConfig *ResourceConfig) *libcontainerconfigs.Resources {
	resources := &libcontainerconfigs.Resources{}
	if resourceConfig == nil {
		return resources
	}
	if resourceConfig.Memory != nil {
		resources.Memory = *resourceConfig.Memory
	}
	if resourceConfig.CpuShares != nil {
		resources.CpuShares = *resourceConfig.CpuShares
	}
	if resourceConfig.CpuQuota != nil {
		resources.CpuQuota = *resourceConfig.CpuQuota
	}
	if resourceConfig.CpuPeriod != nil {
		resources.CpuPeriod = *resourceConfig.CpuPeriod
	}

	// huge page参数提取, 略过
	if utilfeature.DefaultFeatureGate.Enabled(kubefeatures.HugePages) {
    ...
	return resources
}

// ResourceConfigForPod takes the input pod and outputs the cgroup resource config.
func ResourceConfigForPod(pod *v1.Pod) *ResourceConfig {
	// sum requests and limits.
	reqs, limits := resource.PodRequestsAndLimits(pod)

	cpuRequests := int64(0)
	cpuLimits := int64(0)
	memoryLimits := int64(0)
	if request, found := reqs[v1.ResourceCPU]; found {
		cpuRequests = request.MilliValue()
	}
	if limit, found := limits[v1.ResourceCPU]; found {
		cpuLimits = limit.MilliValue()
	}
	if limit, found := limits[v1.ResourceMemory]; found {
		memoryLimits = limit.Value()
	}

	// convert to CFS values
	cpuShares := MilliCPUToShares(cpuRequests)
	cpuQuota, cpuPeriod := MilliCPUToQuota(cpuLimits)
    ...
}

// MilliCPUToShares converts the milliCPU to CFS shares.
func MilliCPUToShares(milliCPU int64) uint64 {
	if milliCPU == 0 {
		// Docker converts zero milliCPU to unset, which maps to kernel default
		// for unset: 1024. Return 2 here to really match kernel default for
		// zero milliCPU.
		return MinShares
	}
	// Conceptually (milliCPU / milliCPUToCPU) * sharesPerCPU, but factored to improve rounding.
	shares := (milliCPU * SharesPerCPU) / MilliCPUToCPU
	if shares < MinShares {
		return MinShares
	}
	return uint64(shares)
}

// MilliCPUToQuota converts milliCPU to CFS quota and period values.
func MilliCPUToQuota(milliCPU int64) (quota int64, period uint64) {
	// CFS quota is measured in two values:
	//  - cfs_period_us=100ms (the amount of time to measure usage across)
	//  - cfs_quota=20ms (the amount of cpu time allowed to be used across a period)
	// so in the above example, you are limited to 20% of a single CPU
	// for multi-cpu environments, you just scale equivalent amounts

	if milliCPU == 0 {
		return
	}

	// we set the period to 100ms by default
	period = QuotaPeriod

	// we then convert your milliCPU to a value normalized over a period
	quota = (milliCPU * QuotaPeriod) / MilliCPUToCPU

	// quota needs to be a minimum of 1ms.
	if quota < MinQuotaPeriod {
		quota = MinQuotaPeriod
	}

	return
}

const (
	// Taken from lmctfy https://github.com/google/lmctfy/blob/master/lmctfy/controllers/cpu_controller.cc
	MinShares     = 2
	SharesPerCPU  = 1024
	MilliCPUToCPU = 1000

	// 100000 is equivalent to 100ms
	QuotaPeriod    = 100000
	MinQuotaPeriod = 1000
)

func setSupportedSubsystems(cgroupConfig *libcontainerconfigs.Cgroup) error {
	for _, sys := range getSupportedSubsystems() {
		if _, ok := cgroupConfig.Paths[sys.Name()]; !ok {
			return fmt.Errorf("Failed to find subsystem mount for subsystem: %v", sys.Name())
		}
        // 调用前面的cgroup.Set()方法
		if err := sys.Set(cgroupConfig.Paths[sys.Name()], cgroupConfig); err != nil {
			return fmt.Errorf("Failed to set config for supported subsystems : %v", err)
		}
	}
	return nil
}

[root@tdc-tester04 ~]# cat /sys/fs/cgroup/cpu/kubepods/burstable/pod4de91174-9002-11e8-a663-ac1f6b83dd66/1cbc69fd7756efdcba38d11a57acab5cdbe0b9b2e5eef2a9e86e3c6c8850b1a1/cpu.shares 
512

[root@tdc-tester04 ~]# cat /sys/fs/cgroup/cpu/kubepods/burstable/pod4de91174-9002-11e8-a663-ac1f6b83dd66/1cbc69fd7756efdcba38d11a57acab5cdbe0b9b2e5eef2a9e86e3c6c8850b1a1/cpu.cfs_quota_us 
100000
[root@tdc-tester04 ~]# cat /sys/fs/cgroup/cpu/kubepods/burstable/pod4de91174-9002-11e8-a663-ac1f6b83dd66/1cbc69fd7756efdcba38d11a57acab5cdbe0b9b2e5eef2a9e86e3c6c8850b1a1/cpu.cfs_period_us 
100000

The CPU resource is measured in cpu units. One cpu, in Kubernetes, is equivalent to:

    1 AWS vCPU
    1 GCP Core
    1 Azure vCore
    1 Hyperthread on a bare-metal Intel processor with Hyperthreading

func Sort(data Interface) {
	n := data.Len()
	if fs, ok := data.(*funcs); ok {
		quickSort_func(fs.lessSwap, 0, n, maxDepth(n))
	} else {
		quickSort(data, 0, n, maxDepth(n))
	}
}

func quickSort(data Interface, a, b, maxDepth int) {
	for b-a > 12 { // Use ShellSort for slices <= 12 elements
		if maxDepth == 0 {
			heapSort(data, a, b)
			return
		}
		maxDepth--
		mlo, mhi := doPivot(data, a, b)
		// Avoiding recursion on the larger subproblem guarantees
		// a stack depth of at most lg(b-a).
		if mlo-a < b-mhi {
			quickSort(data, a, mlo, maxDepth)
			a = mhi // i.e., quickSort(data, mhi, b)
		} else {
			quickSort(data, mhi, b, maxDepth)
			b = mlo // i.e., quickSort(data, a, mlo)
		}
	}
	if b-a > 1 {
		// Do ShellSort pass with gap 6
		// It could be written in this simplified form cause b-a <= 12
		for i := a + 6; i < b; i++ {
			if data.Less(i, i-6) {
				data.Swap(i, i-6)
			}
		}
		insertionSort(data, a, b)
	}
}
// Insertion sort
func insertionSort(data Interface, a, b int) {
	for i := a + 1; i < b; i++ {
		for j := i; j > a && data.Less(j, j-1); j-- {
			data.Swap(j, j-1)
		}
	}
}

// maxDepth returns a threshold at which quicksort should switch
// to heapsort. It returns 2*ceil(lg(n+1)).
func maxDepth(n int) int {
	var depth int
	for i := n; i > 0; i >>= 1 {
		depth++
	}
	return depth * 2
}