Intel 64 and IA-32 Architectures Software Developers Manual Volume 3B, System Programming Guide Part 2

Table Of Contents
Vol. 3 A-51
PERFORMANCE-MONITORING EVENTS
41H 04H UNC_QPI_TX_STALL
ED_MULTI_FLIT.NCS.
LINK_0
Counts cycles the Quickpath
outbound link 0 Non-Coherent
Standard virtual channel is stalled
due to lack of VNA and VN0 credits.
Note that this event does not filter
out when a flit would not have
been selected for arbitration
because another virtual channel is
getting arbitrated.
41H 08H UNC_QPI_TX_STALL
ED_MULTI_FLIT.DRS.
LINK_1
Counts cycles the Quickpath
outbound link 1 Data ResponSe
virtual channel is stalled due to lack
of VNA and VN0 credits. Note that
this event does not filter out when
a flit would not have been selected
for arbitration because another
virtual channel is getting arbitrated.
41H 10H UNC_QPI_TX_STALL
ED_MULTI_FLIT.NCB.
LINK_1
Counts cycles the Quickpath
outbound link 1 Non-Coherent
Bypass virtual channel is stalled
due to lack of VNA and VN0 credits.
Note that this event does not filter
out when a flit would not have
been selected for arbitration
because another virtual channel is
getting arbitrated.
41H 20H UNC_QPI_TX_STALL
ED_MULTI_FLIT.NCS.
LINK_1
Counts cycles the Quickpath
outbound link 1 Non-Coherent
Standard virtual channel is stalled
due to lack of VNA and VN0 credits.
Note that this event does not filter
out when a flit would not have
been selected for arbitration
because another virtual channel is
getting arbitrated.
Table A-3. Non-Architectural Performance Events In the Processor Uncore for Intel
Core i7 Processors
Event
Num.
Umask
Value
Event Mask
Mnemonic Description Comment