Dynamic CPU voltage regulator phase shedding
A voltage regulator phase shedding system includes one or more subsystems to receive a system management interrupt (SMI), gather processor utilization information, determine whether to adjust a performance state, lookup voltage regulator information for new performance state, adjust active voltage regulator phase, and adjust performance state. The voltage regulator phase shedding system can also include one or more subsystems to read a power measurement, calculate throttling requirements, determine whether to adjust a throttling, lookup voltage regulator information for new performance state capacity, adjust active voltage regulator phase, and adjust throttling.
1. A voltage regulator phase adjustment system comprising one or more subsystems to:
determine a first performance state (P-state) of a processor;
use the first P-state to determine that a load of the processor is located at a first efficiency point on a voltage regulator efficiency curve; and
shed at least one active processor voltage regulator phase, wherein, in response to the shedding, the load of the processor shifts to a second efficiency point on the voltage regulator efficiency curve that includes a higher efficiency relative to the first efficiency point.
2. The phase adjustment system of claim 1 , wherein the voltage regulator efficiency curve includes a plurality of efficiency curves.
3. The phase adjustment system of claim 1 , wherein the second efficiency point on the voltage regulator efficiency curve provides a lower power consumption of the processor relative to the first efficiency point.
4. The phase adjustment system of claim 1 , further comprising one or more subsystems to:
determine that the processor is switching to a second P-state that includes a higher load than the first P-state; and
use the voltage regulator efficiency curve to determine that the system will operate more efficiently at the higher load relative to the first P-state if at least one additional active processor voltage regulator phase is enabled and, in response, enabling the at least one additional active processor voltage regulator phase.
5. The phase adjustment system of claim 4 , further comprising one or more subsystems to:
switch the processor to the second P-state subsequent to enabling the at least one active processor voltage regulator phase.
6. The phase adjustment system of claim 1 , further comprising one or more subsystems to:
determine a maximum allowable load for the first P-state, wherein the shedding at least one active processor voltage regulator phase is performed to according to the maximum allowable load.
7. An information handling system (IHS) comprising:
a processor;
memory coupled to the processor; and
a voltage regulator coupled to the processor, wherein the voltage regulator includes a voltage regulator phase adjustment system further comprising one or more subsystems to:
receive an indication that the processor is switching from a first performance state (P-state) to a second P-state;
determine, using a load increase of the processor that is associated with the switch from the first P-state to the second P-state, that the voltage regulator will operate more efficiently at the second P-state relative to the first P-state if at least one additional active processor voltage regulator phase is enabled and,
in response, enable the at least one active processor voltage regulator phase of the voltage regulator; and
switch the processor from the first P-state to the second P-state subsequent to enabling the at least one active processor voltage regulator phase.
8. The IHS of claim 7 , further comprising one or more subsystems to:
determine a third performance P-state of the processor;
use the third P-state to determine that the load of the processor is located at a first efficiency point on a voltage regulator efficiency curve; and
shed at least one active processor voltage regulator phase, wherein, in response to the shedding, the load of the processor shifts to a second efficiency point on the voltage regulator efficiency curve that includes a higher efficiency relative to the first efficiency point.
9. The IHS of claim 7 , further comprising one or more subsystems to:
determine a maximum allowable load for the third P-state, wherein the shedding at least one active processor voltage regulator phase is performed according to the maximum allowable load.
10. A method to adjust voltage regulator phases, the method comprising:
determining a first performance state (P-state) of a processor;
using the first P-state to determine that a load of the processor is located at a first efficiency point on a voltage regulator efficiency curve; and
shedding at least one active processor voltage regulator phase, wherein, in response to the shedding, the load of the processor shifts to a second efficiency point on the voltage regulator efficiency curve that includes a higher efficiency relative to the first efficiency point.
11. The method of claim 10 , further comprising:
determining that the processor is switching to a second P-state that includes a higher load than the first P-state; and
using the voltage regulator efficiency curve to determine that the system will operate more efficiently at the higher load relative to the first P-state if at least one additional active processor voltage regulator phase is enabled and, in response, enabling the at least one additional active processor voltage regulator phase.
12. The method of claim 11 , further comprising:
switching the processor to the second P-state subsequent to enabling the at least one active processor voltage regulator phase.
13. A voltage regulator phase adjustment system comprising one or more subsystems to:
read a power measurement;
calculate throttling requirements using the power measurement;
determine voltage regulator phase efficiency information based on the throttling requirements;
adjust at least one active voltage regulator phase using the voltage regulator phase efficiency information that is based on the throttling requirements; and
perform a throttling operation according to the throttling requirements subsequent to adjusting the at least one active voltage regulator phase.
14. The phase adjustment system of claim 13 , wherein the throttling requirements comprise increasing the throttling.
15. The phase adjustment system of claim 14 , wherein the adjusting the at least one active voltage regulator phase comprises shedding at least one active voltage regulator phase in response to the increased throttling requirements.
16. The phase adjustment system of claim 13 , wherein the throttling requirements comprises decreasing the throttling.
17. The phase adjustment system of claim 16 , wherein the adjusting the at least one active voltage regulator phase comprises enabling at least one active voltage regulator phase in response to the decreased throttling requirements.
18. The phase adjustment system of claim 13 , wherein the system is controlled using a basic input/output system (BIOS).
19. The phase adjustment system of claim 13 , wherein the system is controlled using an operating system.
20. The phase adjustment system of claim 13 , wherein the system is controlled using a basic input/output system (BIOS) and an operating system.