Data processing method and apparatus
Embodiments of this application disclose a data processing method, which can be applied to a clock synchronization network system. The system can correct, based on a clock frequency error or a time error, a data timestamp of a data packet collected by the system in a time period in which there is no reference clock, so that a corrected system time of the data packet is consistent with a reference time. This improves accuracy of data record.
1. A method of data processing, comprising:
receiving, by a processor, a first reference signal before a time period in which there is no reference clock and a second reference signal after the time period;
collecting, by the processor, an i th data packet in the time period; and
adjusting, for providing a working status of the processor, a data timestamp T i of collecting the i th data packet based on error information calculated from the first reference signal and the second reference signal, wherein the error information is a clock frequency error or a time error, the clock frequency error is a difference between a system clock frequency and a reference clock frequency, and the time error is a difference between a system time and a reference time;
wherein i is a positive integer, and T i corresponds to a collection moment of the i th data packet.
2. The method according to claim 1 , wherein the error information is a clock frequency error □ƒ, and □ƒ=ƒ sys −ƒ r is a fixed value, wherein ƒ sys is a system clock frequency corresponding to a moment at which the reference clock is detected again, and ƒ r is a reference clock frequency.
3. The method according to claim 2 , wherein an adjusted data timestamp of the i th data packet is T i ′, and T i ′ satisfies the following:
T i ′=T i −(□ƒ/ƒ sys )× T s ×i , wherein
T s is a sampling cycle.
4. The method according to claim 1 , wherein the error information is a time error T or a time error t, the time error T is a difference between a reference time corresponding to a first moment and a system time corresponding to the first moment, and t satisfies the following:
t=T/K , wherein
the first moment is a moment at which the reference clock is detected again after the i th data packet is collected, and K is a quantity of data packets collected in the time period in which there is no reference clock.
5. The method according to claim 4 , wherein an adjusted data timestamp of the i th data packet is T i ′, and T i ′ satisfies the following:
T i ′=T i −T/K×i , or
T i ′=T i −t×i.
6. The method according to claim 1 , wherein the error information is a clock frequency error □ƒ j , and when a j th data packet is collected, the clock frequency error □ƒ j satisfies the following:
□ƒ j =T s ×S×j , wherein
T s is a sampling cycle, S is an increase rate of the clock frequency error, S is a real number, and j satisfies 0≤j≤i.
7. The method according to claim 6 , wherein an adjusted data timestamp of the i th data packet is T i ′, and T i ′ satisfies the following:
T
i
′
∈
[
T
m
i
n
,
T
m
a
x
]
,
wherein
when
S
≥
0
,
T
m
i
n
=
T
i
-
∑
j
=
0
i
(
(
▯f
j
/
f
sys
,
j
)
×
T
s
)
and
T
m
a
x
=
T
i
-
∑
j
=
0
i
-
1
(
(
▯
f
j
/
f
sys
,
j
)
×
T
s
)
;
or
when
S
≤
0
,
T
m
i
n
=
T
i
-
∑
j
=
0
i
-
1
(
(
▯
f
j
/
f
sys
,
j
)
×
T
s
)
and
T
m
a
x
=
T
i
-
∑
j
=
0
i
(
(
▯
f
j
/
f
sys
,
j
)
×
T
s
)
;
wherein ƒ sys,j is a system clock frequency corresponding to a moment at which the j th data packet is collected.
8. The method according to claim 1 , wherein
the error information is a clock frequency error □ƒ j of the data packet; and
□ƒ j is determined based on a correspondence between a locally stored clock frequency error of the data packet collected by the system in the time period in which there is no reference clock and a sampling condition.
9. The method according to claim 8 , wherein an adjusted data timestamp of the i th data packet is T i ′, and T i ′ satisfies the following:
T
i
′
=
T
i
-
∑
j
=
0
i
(
(
▯
f
j
/
f
sys
,
j
)
×
T
s
)
,
wherein
T s is a sampling cycle, ƒ sys,j is a system clock frequency corresponding to a moment at which a j th data packet is collected, and j satisfies 0≤j≤i.
10. A data processing apparatus, comprising:
at least one processor; and
a memory coupled to the at least one processor and storing program codes, which when executed by the at least one processor, cause the data processing apparatus to perform operations, the operations comprising:
receiving, by the at least one processor, a first reference signal before a time period in which there is no reference clock and a second reference signal after the time period;
collecting, by the at least one processor, an i th data packet in the time period; and
adjusting, for providing a working status of the at least one processor, a data timestamp T i of collecting the i th data packet based on error information calculated from the first reference signal and the second reference signal, wherein the error information is a clock frequency error or a time error, the clock frequency error is a difference between a system clock frequency and a reference clock frequency, and the time error is a difference between a system time and a reference time;
wherein i is a positive integer, and T i corresponds to a collection moment of the i th data packet.
11. The data processing apparatus according to claim 10 , wherein the error information is a clock frequency error □ƒ, and □ƒ=ƒ sys −ƒ r is a fixed value, wherein ƒ sys is a system clock frequency corresponding to a moment at which the reference clock is detected again, and ƒ r is a reference clock frequency.
12. The data processing apparatus according to claim 11 , wherein an adjusted data timestamp of the i th data packet is T i ′, and T i ′ satisfies the following:
T i ′=T i −(□ƒ/ƒ sys )× T s ×i , wherein
T s is a sampling cycle.
13. The data processing apparatus according to claim 10 , wherein the error information is a time error T or a time error t, the time error T is a difference between a reference time corresponding to a first moment and a system time corresponding to the first moment, and t satisfies the following:
t=T/K , wherein
the first moment is a moment at which the reference clock is detected again after the i th data packet is collected, and K is a quantity of data packets collected in the time period in which there is no reference clock.
14. The data processing apparatus according to claim 13 , wherein an adjusted data timestamp of the i th data packet is T i ′, and T i ′ satisfies the following:
T i ′=T i −T/K×i , or
T i ′=T i −t×i.
15. The data processing apparatus according to claim 10 , wherein the error information is a clock frequency error □ƒ j , and when a j th data packet is collected, the clock frequency error □ƒ j satisfies the following:
□ƒ j =T s ×S×j , wherein
T s is a sampling cycle, S is an increase rate of the clock frequency error, S is a real number, and j satisfies 0≤j≤i.
16. The data processing apparatus according to claim 15 , wherein an adjusted data timestamp of the i th data packet is T i ′, and T i ′ satisfies the following:
T
i
′
∈
[
T
m
i
n
,
T
m
a
x
]
,
wherein
when
S
≥
0
,
T
m
i
n
=
T
i
-
∑
j
=
0
i
(
(
▯
f
j
/
f
sys
,
j
)
×
T
s
)
and
T
m
a
x
=
T
i
-
∑
j
=
0
i
-
1
(
(
▯
f
j
/
f
sys
,
j
)
×
T
s
)
;
or
when
S
≤
0
,
T
m
i
n
=
T
i
-
∑
j
=
0
i
-
1
(
(
▯
f
j
/
f
sys
,
j
)
×
T
s
)
and
T
m
a
x
=
T
i
-
∑
j
=
0
i
(
(
▯f
j
/
f
sys
,
j
)
×
T
s
)
;
wherein ƒ sys,j is a system clock frequency corresponding to a moment at which the j th data packet is collected.
17. The data processing apparatus according to claim 10 , wherein the error information is a clock frequency error □ƒ j of the data packet; and □ƒ j is determined based on a correspondence between a locally stored clock frequency error of the data packet collected by the system in the time period in which there is no reference clock and a sampling condition.
18. The data processing apparatus according to claim 17 , wherein an adjusted data timestamp of the i th data packet is T i ′, and T i ′ satisfies the following:
T
i
′
=
T
i
-
∑
j
=
0
i
(
(
▯
f
j
/
f
sys
,
j
)
×
T
s
)
,
wherein
T s is a sampling cycle, ƒ sys,j is a system clock frequency corresponding to a moment at which a j th data packet is collected, and j satisfies 0≤j≤i.
19. A non-transitory computer-readable storage medium, comprising a program or instructions, which when run on a computer, cause the computer to perform operations, the operations comprising:
receiving a first reference signal before a time period in which there is no reference clock and a second reference signal after the time period;
collecting an i th data packet in the time period; and
adjusting, for providing a working status, a data timestamp T i of collecting the i th data packet based on error information calculated from the first reference signal and the second reference signal, wherein the error information is a clock frequency error or a time error, the clock frequency error is a difference between a system clock frequency and a reference clock frequency, and the time error is a difference between a system time and a reference time;
wherein i is a positive integer, and T i corresponds to a collection moment of the i th data packet.
20. The non-transitory computer-readable storage medium of claim 19 , wherein the error information is a clock frequency error □ƒ, and □ƒ=ƒ sys −ƒ r is a fixed value, wherein ƒ sys is a system clock frequency corresponding to a moment at which the reference clock is detected again, and ƒ r is a reference clock frequency.