libnvme(9) API Manual libnvme(9)

# [NAME](#NAME)

struct nvme\_power\_meas\_log - Power Measurement Log Page (Log Identifier 25h)

# [SYNOPSIS](#SYNOPSIS)

struct nvme\_power\_meas\_log {  
**\_\_u8 ver;**  
**\_\_u8 pmgn;**  
**\_\_le16 pma;**  
**\_\_le32 sze;**  
**\_\_le32 pmc;**  
**\_\_le16 nphd;**  
**\_\_le16 smtr;**  
**struct nvme\_timestamp smts;**  
**\_\_le16 phds;**  
**\_\_le16 phbs;**  
**\_\_le16 nphds;**  
**\_\_le16 vss;**  
**\_\_le32 phdoc;**  
**\_\_u8 rsvd36\[4];**  
**\_\_le32 aipwr;**  
**\_\_le32 mipwr;**  
**struct nvme\_timestamp mipwrt;**  
**\_\_u8 ipwrpe;**  
**\_\_u8 rsvd57\[7];**  
**struct nvme\_power\_histogram\_desc descs\[];**  
};

# [Members](#Members)

[ver](#ver)

Version. Shall be cleared to 0h.

[pmgn](#pmgn)

Power Measurement Generation Number. Incremented each time a Set Features command with Action = 1h (Start Power Measurements) is successfully completed. Rolls over from FFh to 0h.

[pma](#pma)

Power Measurement Attributes. See *enum nvme\_pma*.

[sze](#sze)

Size. Indicates the size of this log page in bytes.

[pmc](#pmc)

Power Measurement Count. Number of interval power measurements collected. Does not wrap after FFFFFFFFh. Cleared to 0h when Start Power Measurements succeeds or if no measurement has occurred.

[nphd](#nphd)

Number of Power Histogram Descriptors in this log page.

[smtr](#smtr)

Stop Measurement Time Remaining. Time remaining in minutes until controller stops collecting interval power measurements. 0h means not specified.

[smts](#smts)

Stop Measurement Timestamp. Timestamp of when interval power measurements stopped being collected. See *struct nvme\_timestamp*.

[phds](#phds)

Power Histogram Descriptor Size. Size in bytes of each descriptor.

[phbs](#phbs)

Power Histogram Bin Size. Size in milliwatts of each bin. Shall be set to 250 milliwatts.

[nphds](#nphds)

Number of Power Histogram Descriptors Supported. Maximum number of descriptors that can be reported. If 0h, NPHD shall be cleared to 0h and no descriptors are reported.

[vss](#vss)

Vendor Specific Size. Size in bytes of the Vendor Specific field.

[phdoc](#phdoc)

Power Histogram Descriptor Overflow Count. Number of interval power measurements greater than the maximum power indicated by the last Power Histogram Descriptor. Does not wrap after FFFFFFFFh.

[rsvd36](#rsvd36)

Reserved.

[aipwr](#aipwr)

Average Interval Power. Bits 31:18 are reserved. Bits 17:16 contain the Power Scale (PWRS); see *enum nvme\_psd\_ps*. Bits 15:0 contain the Power Value (PWRV).

[mipwr](#mipwr)

Maximum Interval Power. Bits 31:18 are reserved. Bits 17:16 contain the Power Scale (PWRS); see *enum nvme\_psd\_ps*. Bits 15:0 contain the Power Value (PWRV).

[mipwrt](#mipwrt)

Maximum Interval Power Timestamp. Timestamp of when the maximum interval power was collected. See *struct nvme\_timestamp*.

[ipwrpe](#ipwrpe)

Interval Power Percent Error. Maximum percent error (0-100%). Values 101-254 reserved. 255 indicates not reported.

[rsvd57](#rsvd57)

Reserved.

[descs](#descs)

Power Histogram Descriptors (*struct nvme\_power\_histogram\_desc*).

struct nvme\_power\_meas\_log October 2026

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Document: nvme_power_meas_log-libnvme3(2) from nvme-cli 3.2-r0 (Chainguard OS)
Source: https://github.com/linux-nvme/nvme-cli