github.com/Ilhicas/nomad@v1.0.4-0.20210304152020-e86851182bc3/client/fingerprint/cpu.go (about)

     1  package fingerprint
     2  
     3  import (
     4  	"fmt"
     5  
     6  	log "github.com/hashicorp/go-hclog"
     7  	"github.com/hashicorp/nomad/helper/stats"
     8  	"github.com/hashicorp/nomad/nomad/structs"
     9  )
    10  
    11  const (
    12  	// defaultCPUTicks is the default amount of CPU resources assumed to be
    13  	// available if the CPU performance data is unable to be detected. This is
    14  	// common on EC2 instances, where the env_aws fingerprinter will follow up,
    15  	// setting an accurate value.
    16  	defaultCPUTicks = 1000 // 1 core * 1 GHz
    17  )
    18  
    19  // CPUFingerprint is used to fingerprint the CPU
    20  type CPUFingerprint struct {
    21  	StaticFingerprinter
    22  	logger log.Logger
    23  }
    24  
    25  // NewCPUFingerprint is used to create a CPU fingerprint
    26  func NewCPUFingerprint(logger log.Logger) Fingerprint {
    27  	f := &CPUFingerprint{logger: logger.Named("cpu")}
    28  	return f
    29  }
    30  
    31  func (f *CPUFingerprint) Fingerprint(req *FingerprintRequest, resp *FingerprintResponse) error {
    32  	cfg := req.Config
    33  	setResourcesCPU := func(totalCompute int) {
    34  		// COMPAT(0.10): Remove in 0.10
    35  		resp.Resources = &structs.Resources{
    36  			CPU: totalCompute,
    37  		}
    38  
    39  		resp.NodeResources = &structs.NodeResources{
    40  			Cpu: structs.NodeCpuResources{
    41  				CpuShares: int64(totalCompute),
    42  			},
    43  		}
    44  	}
    45  
    46  	if err := stats.Init(); err != nil {
    47  		f.logger.Warn("failed initializing stats collector", "error", err)
    48  	}
    49  
    50  	if modelName := stats.CPUModelName(); modelName != "" {
    51  		resp.AddAttribute("cpu.modelname", modelName)
    52  	}
    53  
    54  	if mhz := stats.CPUMHzPerCore(); mhz > 0 {
    55  		resp.AddAttribute("cpu.frequency", fmt.Sprintf("%.0f", mhz))
    56  		f.logger.Debug("detected cpu frequency", "MHz", log.Fmt("%.0f", mhz))
    57  	}
    58  
    59  	if numCores := stats.CPUNumCores(); numCores > 0 {
    60  		resp.AddAttribute("cpu.numcores", fmt.Sprintf("%d", numCores))
    61  		f.logger.Debug("detected core count", "cores", numCores)
    62  	}
    63  
    64  	tt := int(stats.TotalTicksAvailable())
    65  	if cfg.CpuCompute > 0 {
    66  		f.logger.Debug("using user specified cpu compute", "cpu_compute", cfg.CpuCompute)
    67  		tt = cfg.CpuCompute
    68  	}
    69  
    70  	// If we cannot detect the cpu total compute, fallback to a very low default
    71  	// value and log a message about configuring cpu_total_compute. This happens
    72  	// on Graviton instances where CPU information is unavailable. In that case,
    73  	// the env_aws fingerprinter updates the value with correct information.
    74  	if tt == 0 {
    75  		f.logger.Info("fallback to default cpu total compute, set client config option cpu_total_compute to override")
    76  		tt = defaultCPUTicks
    77  	}
    78  
    79  	resp.AddAttribute("cpu.totalcompute", fmt.Sprintf("%d", tt))
    80  	setResourcesCPU(tt)
    81  	resp.Detected = true
    82  
    83  	return nil
    84  }