Reference Number: 327043-001
131
Intel® Xeon® Processor E5-2600 Product Family Uncore Performance Monitoring
can be transmitted, as those holding VN0 credits will still (potentially) be able to transmit. Gener-
ally it is the goal of the uncore that VNA credits should not run out, as this can substantially throttle
back useful Intel® QPI bandwidth.
VNA_CREDIT_CYCLES_USED
• Title:
Cycles with 1 or more VNA credits in use
• Category:
LINK_VNA_CREDITS Events
• Event Code:
0x32
• Max. Inc/Cyc:
1,
Register Restrictions:
0-1
• Definition:
Number of Intel® QPI uclk cycles with one or more VNA credits in use. This event can
be used in conjunction with the VNA In-Use Accumulator to calculate the average number of used
VNA credits.
2.10
Packet Matching Reference
In the Intel® QPI Link Layer, the performance monitoring infrastructure allows a user to filter packet
traffic according to certain fields. A couple common fields, the Message Class/Opcode fields, have
been summarized in the following tables.
Table 2-142. Intel® QuickPath Interconnect Packet Message Classes
Code
Name
Definition
b0000
HOM0
Home - Requests
b0001
HOM1
Home - Responses
b0010
NDR
Non-Data Responses
b0011
SNP
Snoops
b0100
NCS
Non-Coherent Standard
---
b1100
NCB
Non-Coherent Bypass
---
b1110
DRS
Data Response
Table 2-143. Opcode Match by Message Class (Sheet 1 of 2)
Opc
HOM0
HOM1
SNP
DRS
0000 RdCur
RspI
SnpCur
DataC_(FEIMS)
0001 RdCode
RspS
SnpCode
DataC_(FEIMS)_FrcAck
Cnflt
0010 RdData
---
SnpData
DataC_(FEIMS)_Cmp
0011 NonSnpRd
---
---
DataNc
0100 RdInvOwn
RspCnflt
SnpInvOwn
WbIData
0101 InvXtoI
---
SnpInvXtoI
WbSData
0110 EvctCln
RspCnfltOwn
---
WbEData
0111 NonSnpWr
---
---
NonSnpWrData
1000 InvItoE
RspFwd
SnpInvItoE
WbIDataPtl
1001 AckCnfltWbI
RspFwdI
---
---
1010 ---
RspFwdS
---
WbEDataPtl
1011 ---
RspFwdIWb
---
NonSnpWrdataPtl
1100 WbMtoI
RspFwdSWb
---
---
