Uncore Manual

Uncore Performance Monitoring
Home Agent (HA) Performance Monitoring
72 Reference Number: 329468-002
TAD_REQUESTS_G0
• Title: HA Requests to a TAD Region - Group 0
• Category: TAD Events
• Event Code: 0x1b
• Max. Inc/Cyc:. 2, Register Restrictions: 0-3
• Definition: Counts the number of HA requests to a given TAD region. There are up to 11 TAD (tar-
get address decode) regions in each home agent. All requests destined for the memory controller
must first be decoded to determine which TAD region they are in. This event is filtered based on the
TAD region ID, and covers regions 0 to 7. This event is useful for understanding how applications
are using the memory that is spread across the different memory regions. It is particularly useful
for “Monroe” systems that use the TAD to enable individual channels to enter self-refresh to save
power.
Table 2-62. Unit Masks for SNP_RESP_RECV_LOCAL
Extension
umask
[15:8]
Description
RSPI bxxxxxxx1 RspI
Filters for snoops responses of RspI. RspI is returned when the
remote cache does not have the data, or when the remote cache
silently evicts data (such as when an RFO hits non-modified
data).
RSPS bxxxxxx1x RspS
Filters for snoop responses of RspS. RspS is returned when a
remote cache has data but is not forwarding it. It is a way to let
the requesting socket know that it cannot allocate the data in E
state. No data is sent with S RspS.
RSPIFWD bxxxxx1xx RspIFwd
Filters for snoop responses of RspIFwd. This is returned when a
remote caching agent forwards data and the requesting agent is
able to acquire the data in E or M states. This is commonly
returned with RFO transactions. It can be either a HitM or a
HitFE.
RSPSFWD bxxxx1xxx RspSFwd
Filters for a snoop response of RspSFwd. This is returned when a
remote caching agent forwards data but holds on to its current
copy. This is common for data and code reads that hit in a
remote socket in E or F state.
RSPxWB bxxx1xxxx Rsp*WB
Filters for a snoop response of RspIWB or RspSWB. This is
returned when a non-RFO request hits in M state. Data and Code
Reads can return either RspIWB or RspSWB depending on how
the system has been configured. InvItoE transactions will also
return RspIWB because they must acquire ownership.
RSPxFWDxWB bxx1xxxxx Rsp*FWD*WB
Filters for a snoop response of Rsp*Fwd*WB. This snoop
response is only used in 4s systems. It is used when a snoop
HITM's in a remote caching agent and it directly forwards data to
a requestor, and simultaneously returns data to the home to be
written back to memory.
RSPCNFLCT bx1xxxxxx RspCnflct
Filters for snoops responses of RspConflict. This is returned when
a snoop finds an existing outstanding transaction in a remote
caching agent when it CAMs that caching agent. This triggers
conflict resolution hardware. This covers both RspCnflct and
RspCnflctWbI.
OTHER b1xxxxxxx Other
Filters for all other snoop responses.