Uncore Manual
Reference Number: 329468-002 59
Uncore Performance Monitoring
Home Agent (HA) Performance Monitoring
•iMC RPQ/WPQ Events
Determine cycles the HA is stuck without credits in to the iMCs read/write queues.
2.4.3.1 On the Major HA Structures:
The 128-entry TF (Tracker File) holds all transactions that arrive in the HA from the time they arrive
until they are completed and leave the HA. Transactions could stay in this structure much longer than
they are needed. TF is the critical resource each transaction needs before being sent to the iMC
(memory controller)
TF average occupancy == (valid cnt * 128 / cycles)
TF average latency == (valid cnt * 128 / inserts)
Other Internal HA Queues of Interest:
TxR (aka EGR) - The HA has Egress (responses) queues for each ring (AD, AK, BL) as well as queues
to track credits the HA has to push traffic onto those rings.
2.4.4 HA Box Events Ordered By Code
The following table summarizes the directly measured HA Box events.
Symbol Name
Event
Code
Ctrs
Max
Inc/
Cyc
Description
CLOCKTICKS 0x00 0-3 1 uclks
REQUESTS 0x01 0-3 1 Read and Write Requests
CONFLICT_CYCLES 0x0b 0-3 1 Conflict Checks
DIRECTORY_LOOKUP 0x0c 0-3 1 Directory Lookups
DIRECTORY_UPDATE 0x0d 0-3 1 Directory Updates
TxR_AK 0x0e 0-3 1 Outbound Ring Transactions on AK
TxR_BL 0x10 0-3 1 Outbound DRS Ring Transactions to
Cache
DIRECT2CORE_COUNT 0x11 0-3 1 Direct2Core Messages Sent
DIRECT2CORE_CYCLES_DISABLED 0x12 0-3 1 Cycles when Direct2Core was Disabled
DIRECT2CORE_TXN_OVERRIDE 0x13 0-3 1 Number of Reads that had Direct2Core
Overridden
BYPASS_IMC 0x14 0-3 1 HA to iMC Bypass
RPQ_CYCLES_NO_REG_CREDITS 0x15 0-3 4 iMC RPQ Credits Empty - Regular
IMC_READS 0x17 0-3 4 HA to iMC Normal Priority Reads Issued
WPQ_CYCLES_NO_REG_CREDITS 0x18 0-3 4 HA iMC CHN0 WPQ Credits Empty -
Regular
IMC_WRITES 0x1a 0-3 1 HA to iMC Full Line Writes Issued
TAD_REQUESTS_G0 0x1b 0-3 2 HA Requests to a TAD Region - Group 0
TAD_REQUESTS_G1 0x1c 0-3 2 HA Requests to a TAD Region - Group 1
IMC_RETRY 0x1e 0-3 1 Retry Events
ADDR_OPC_MATCH 0x20 0-3 1 QPI Address/Opcode Match
SNOOP_RESP 0x21 0-3 1 Snoop Responses Received
IGR_NO_CREDIT_CYCLES 0x22 0-3 1 Cycles without QPI Ingress Credits