计算平均非内核请求延迟计算

Average Offcore Request Latency Measurement

Measurement of average latency of offcore transaction requests can be enabled using MSR_OFFCORE_RSP0.[bit 38] with the choice of request type specified in MSR_OFFCORE_RSP0.[bit 15:0] and MSR_OFFCORE_RSP0.[bit 37:16] set to 0.

When average latency measurement is enabled, e.g. with IA32_PERFEVTSEL0.[bits 15:0] = 0x01B7 and chosen value of MSR_OFFCORE_RSP0, IA32_PMC0 will accumulate weighted cycles of outstanding transaction requests for the specified transaction request type. At the same time, IA32_PMC1 will accumulated the number of occurrences each time a new transaction request of specified type is made.

OFFCORE_REQUESTS_OUTSTANDING：累计计算非内核请求的周期数cycles

OFFCORE_REQUESTS：累计计算非内核请求的次数