Discovery CPU details for default thread selection (#6264)

On windows, detect large multi-socket systems and reduce to the number of cores
in one socket for best performance

gpu/types.go

@@ -10,11 +10,11 @@ import (
 type memInfo struct {
 	TotalMemory uint64 `json:"total_memory,omitempty"`
 	FreeMemory  uint64 `json:"free_memory,omitempty"`
-	FreeSwap    uint64 `json:"free_swap,omitempty"`
+	FreeSwap    uint64 `json:"free_swap,omitempty"` // TODO split this out for system only
 }
 
 // Beginning of an `ollama info` command
-type GpuInfo struct {
+type GpuInfo struct { // TODO better name maybe "InferenceProcessor"?
 	memInfo
 	Library string `json:"library,omitempty"`
 
@@ -49,6 +49,17 @@ type GpuInfo struct {
 
 type CPUInfo struct {
 	GpuInfo
+	CPUs []CPU
+}
+
+// CPU type represents a CPU Package occupying a socket
+type CPU struct {
+	ID                  string `cpuinfo:"processor"`
+	VendorID            string `cpuinfo:"vendor_id"`
+	ModelName           string `cpuinfo:"model name"`
+	CoreCount           int
+	EfficiencyCoreCount int // Performance = CoreCount - Efficiency
+	ThreadCount         int
 }
 
 type CudaGPUInfo struct {
@@ -158,3 +169,12 @@ type SystemInfo struct {
 	UnsupportedGPUs []UnsupportedGPUInfo `json:"unsupported_gpus"`
 	DiscoveryErrors []string             `json:"discovery_errors"`
 }
+
+// Return the optimal number of threads to use for inference
+func (si SystemInfo) GetOptimalThreadCount() int {
+	if len(si.System.CPUs) == 0 {
+		return 0
+	}
+	// Allocate thread count matching the performance cores on a single socket
+	return si.System.CPUs[0].CoreCount - si.System.CPUs[0].EfficiencyCoreCount
+}