Intel® Xeon® Processor E5-2600 Product Family Uncore Performance Monitoring
62
Reference Number: 327043-001
All MC performance monitor data registers are 48-bit wide. Should a counter overflow (a carry out
from bit 47), the counter will wrap and continue to collect events.
If accessible, software can continuously read the data registers without disabling event collection.
This is a counter that always tracks the number of DRAM clocks (dclks - half of DDR speed) in the iMC.
The dclk never changes frequency (on a given system), and therefore is a good measure of wall clock
(unlike the Uncore clock which can change frequency based on system load). This clock is generally a
bit slower than the uclk (~800MHz to ~1.066GHz) and therefore has less fidelity.
2.5.5
iMC Performance Monitoring Events
2.5.5.1
An Overview:
A sampling of events available for monitoring in the iMC:
•
Translated commands
: Various Read and Write CAS commands
•
Memory commands
: CAS, Precharge, Refresh, Preemptions, etc,
• Page hits and page misses.
•
Page Closing
Events
•
Control of power consumption
:
Thermal Throttling by Rank, Time spent in CKE ON mode,
etc.
and many more.
Internal iMC Queues:
Table 2-62. MC_CHy_PCI_PMON_FIXED_CTL Register – Field Definitions
Field
Bits
Attr
HW
Reset
Val
Description
rsv
31:24
RV
0 Reserved (?)
rsv
23
RV
0 Reserved. SW must write to 0 else behavior is undefined.
en
22
RW-V
0 Local Counter Enable.
rsv
21:20
RV
0 Reserved. SW must write to 0 else behavior is undefined.
rst
19
WO
0 When set to 1, the corresponding counter will be cleared to 0.
rsv
18:0
RV
0 Reserved (?)
Table 2-63. MC_CHy_PCI_PMON_CTR{FIXED,3-0} Register – Field Definitions
Field
Bits
Attr
HW
Reset
Val
Description
rsv
63:48
RV
0 Reserved (?)
event_count
47:0
RW-V
0 48-bit performance event counter
