在Lazarus中分析Windows和Linux的延时

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前言

之前用Delphi时，研究过延时及其时间精度，并写了篇文章——Delphi中的延时，当时是仅在windows平台下测试的，现在想用Lazarus分别在windows和linux平台测试对比下。

测试

测试环境

• CPU：x86_64

• win：win10

• linux：debian 12.6 + xfce

• ide：Lazarus 3.4 + fpc 3.2.2

测试设计

整体与之前的设计保持一致，增加了GetTickCount64的测试，Timer的测试有改动，具体如下：

1. 假定系统时间是足够精确的，因此使用Now分别在延时前后获取系统当前时间来进行耗时评估。

2. 为使测试更具代表性，每个测试点连续测试100次，取算术平均值。

3. 在1ms~100ms内，测试点步长为1ms，在100ms~1000ms内，测试点步长为10ms。

4. 为尽可能减小干扰，测试过程中未使用并行，Sleep、GetTickCount和GetTickCount64未使用Application.ProcessMessages;，Timer绕不开事件触发，使用了Application.ProcessMessages;。

测试结果

windows

延时(ms)	Sleep	GetTickCount	GetTickCount64	Timer
1	1.93	15.51	15.63	15.62
2	2.93	16.59	15.62	15.63
3	3.95	15.58	15.62	15.66
4	5.10	15.49	15.94	15.61
5	5.86	15.55	15.62	15.65
6	6.83	15.50	15.62	15.63
7	7.81	15.62	15.63	15.67
8	8.77	15.55	15.63	15.68
9	9.76	15.50	15.63	15.64
10	10.77	15.59	15.63	15.62
11	11.71	15.48	15.63	15.63
12	12.71	15.56	15.63	15.63
13	13.68	15.54	15.61	15.63
14	14.69	15.63	15.62	15.62
15	15.70	15.56	15.62	15.62
16	16.59	24.82	25.00	25.02
17	17.60	31.11	31.25	31.26
18	18.59	31.24	31.25	31.24
19	19.56	31.22	31.26	31.25
20	20.56	31.16	31.25	31.26
21	21.53	31.11	31.25	31.27
22	22.50	31.21	31.26	31.24
23	23.45	31.21	31.24	31.29
24	24.58	31.16	31.25	31.25
25	25.44	31.12	31.26	31.24
26	27.20	31.23	31.24	31.25
27	27.54	31.21	31.25	31.24
28	28.34	31.19	31.26	31.26
29	30.06	31.15	31.25	31.25
30	30.38	31.18	31.25	31.27
31	31.34	31.14	31.25	31.26
32	32.31	41.59	41.72	41.56
33	33.33	46.83	46.88	46.87
34	34.30	46.78	46.87	46.89
35	35.29	46.72	46.88	46.88
36	36.35	46.77	46.88	46.86
37	37.43	46.78	46.87	46.91
38	38.51	46.75	46.88	46.89
39	39.56	46.80	46.86	46.88
40	40.79	46.86	46.87	46.91
41	41.92	46.79	46.87	46.88
42	42.92	46.75	46.87	47.23
43	44.03	48.28	46.87	46.87
44	47.16	46.74	46.88	46.91
45	46.67	46.72	46.87	46.92
46	48.00	46.81	46.89	46.84
47	47.85	49.92	50.01	50.00
48	48.98	62.41	62.50	62.50
49	49.68	62.98	63.59	62.50
50	50.73	63.18	62.65	62.51
51	51.90	62.46	62.50	62.54
52	52.75	62.37	62.47	62.50
53	57.09	63.79	62.41	62.50
54	55.96	63.22	64.07	62.50
55	58.24	63.64	63.44	62.49
56	56.64	62.56	62.51	62.53
57	59.31	62.36	62.49	62.61
58	58.86	62.45	62.50	62.51
59	59.61	62.41	63.26	62.52
60	60.63	62.46	62.50	62.83
61	68.70	64.06	66.70	62.51
62	63.70	62.36	62.65	62.55
63	66.46	75.67	75.00	75.00
64	65.40	80.31	78.13	78.11
65	65.59	78.75	78.11	78.14
66	67.53	78.08	78.28	78.13
67	67.42	78.04	78.01	78.13
68	68.45	78.11	80.20	78.11
69	70.19	78.21	79.77	78.08
70	72.36	78.07	78.13	78.14
71	71.68	77.98	78.60	78.12
72	72.54	78.09	78.12	78.16
73	73.31	78.06	78.12	78.12
74	74.31	78.04	78.43	78.16
75	75.42	82.67	81.39	78.17
76	76.39	78.25	78.13	78.11
77	78.34	78.06	78.28	78.14
78	80.03	78.42	78.11	78.13
79	79.38	93.73	93.75	93.76
80	80.58	93.63	93.75	93.76
81	81.37	93.61	93.74	93.96
82	95.52	93.90	94.51	94.08
83	89.44	94.43	93.76	93.89
84	85.00	97.95	94.04	93.75
85	87.29	93.68	93.72	93.79
86	88.90	94.03	93.75	93.90
87	87.92	93.61	93.75	93.91
88	89.34	93.63	93.74	93.75
89	89.78	93.65	93.75	93.76
90	90.90	95.81	93.90	96.11
91	91.69	93.52	93.81	93.79
92	92.71	93.66	93.75	93.71
93	93.71	93.64	94.30	93.82
94	94.76	99.93	102.50	100.02
95	95.72	109.55	110.47	109.53
96	114.63	109.25	111.25	109.69
97	97.64	109.59	109.38	109.38
98	98.78	109.81	109.69	109.37
99	99.58	109.48	109.37	109.39
100	100.67	109.30	109.38	109.43
110	110.56	124.69	125.00	125.01
120	120.28	125.03	125.14	125.01
130	130.84	140.70	141.24	140.67
140	144.30	140.66	140.63	140.66
150	150.49	156.18	156.25	156.29
160	160.38	171.76	172.66	171.90
170	174.50	172.81	171.88	171.87
180	180.58	187.39	187.50	187.50
190	190.55	203.04	203.19	203.06
200	200.89	203.32	203.12	203.12
210	210.93	218.76	218.75	218.75
220	220.72	234.28	234.37	235.16
230	230.93	234.23	234.38	234.39
240	240.86	249.89	249.98	250.03
250	250.85	249.91	250.00	249.99
260	261.73	266.03	265.63	265.60
270	270.52	281.20	281.25	281.23
280	280.56	281.16	281.24	281.24
290	290.63	296.86	296.87	296.86
300	300.77	312.35	312.49	312.50
310	310.53	312.43	312.50	312.51
320	320.62	328.13	328.12	328.12
330	330.43	343.64	343.75	343.74
340	340.75	343.63	343.75	343.81
350	350.57	359.36	359.37	359.48
360	360.85	374.83	375.00	375.01
370	370.53	374.93	375.00	375.01
380	380.80	390.60	390.63	390.64
390	390.51	390.56	390.62	390.63
400	400.59	406.28	406.26	406.25
410	410.53	421.81	421.88	421.88
420	420.67	421.82	421.88	421.94
430	430.51	437.39	437.50	437.53
440	440.56	453.00	453.13	453.12
450	450.90	453.01	453.12	453.12
460	460.67	468.71	468.74	468.73
470	470.56	484.29	484.37	484.37
480	480.61	484.24	484.37	484.38
490	490.58	499.88	500.01	500.03
500	500.59	499.85	500.00	500.02
510	510.64	515.59	515.62	515.63
520	520.52	531.17	531.26	531.27
530	530.78	531.22	531.26	531.26
540	540.54	546.79	546.88	546.92
550	550.83	562.40	562.50	562.50
560	560.48	562.49	562.50	562.53
570	570.57	578.00	578.12	578.13
580	580.58	593.63	593.75	593.76
590	590.58	593.63	593.75	593.75
600	600.51	609.34	609.37	609.43
610	610.67	624.90	625.00	625.00
620	620.53	624.94	624.99	625.04
630	630.61	640.59	640.63	640.66
640	640.91	640.61	640.63	640.63
650	650.99	656.19	656.25	656.29
660	660.58	671.88	671.88	671.87
670	670.65	671.85	671.88	671.89
680	680.55	687.40	687.50	687.53
690	690.72	703.00	703.13	703.12
700	700.59	703.00	703.13	703.13
710	710.66	718.71	718.75	718.75
720	720.68	734.30	734.38	734.36
730	730.59	734.25	734.37	734.44
740	740.51	749.90	750.00	750.04
750	750.71	749.88	749.89	750.01
760	767.71	767.43	765.60	765.71
770	772.40	782.20	785.29	783.42
780	782.34	781.16	781.20	781.26
790	791.15	796.82	798.25	796.92
800	802.97	814.65	814.25	812.50
810	821.12	860.42	814.70	813.61
820	822.23	828.34	828.12	828.17
830	832.87	843.64	843.90	843.75
840	842.62	843.48	843.90	843.74
850	851.14	859.29	859.38	859.37
860	865.43	874.82	874.91	875.00
870	870.97	874.97	874.98	874.99
880	881.05	891.12	890.63	890.62
890	891.07	890.59	890.61	890.88
900	901.54	906.18	906.40	906.29
910	911.32	924.00	922.41	922.03
920	921.20	921.88	923.91	922.05
930	930.63	937.62	937.51	937.50
940	940.81	953.09	953.12	953.12
950	950.94	953.12	953.13	953.14
960	960.62	968.90	968.74	968.79
970	970.56	984.24	984.38	984.36
980	980.67	984.33	984.37	984.44
990	990.63	999.93	1000.00	1000.00
1000	1000.60	999.86	1000.00	1000.00

linux

延时(ms)	Sleep	GetTickCount	GetTickCount64	Timer
1	1.38	1.03	1.11	1.48
2	2.67	2.10	2.16	2.15
3	3.57	3.23	3.18	3.36
4	4.49	4.02	4.32	4.13
5	5.54	5.27	5.52	5.38
6	6.73	6.12	6.20	6.33
7	7.57	7.41	7.27	7.28
8	8.52	8.16	8.11	8.21
9	9.52	9.17	9.16	9.51
10	10.46	10.40	10.28	10.65
11	11.52	11.17	11.29	11.48
12	12.70	12.06	12.13	12.65
13	13.50	13.61	13.27	13.29
14	14.83	14.32	14.08	16.12
15	15.50	15.07	15.54	15.45
16	16.51	16.09	16.08	16.10
17	17.60	17.15	17.06	17.31
18	18.47	18.15	18.10	18.88
19	19.46	19.23	19.15	19.49
20	20.47	20.20	20.07	20.47
21	21.50	21.21	21.47	21.45
22	22.42	22.08	22.08	22.32
23	23.59	23.13	23.30	23.36
24	24.43	24.19	24.10	24.25
25	25.46	25.11	25.13	25.35
26	26.50	26.23	26.10	26.33
27	27.43	27.08	27.09	27.32
28	28.39	28.32	28.05	28.26
29	29.57	29.15	29.20	29.14
30	30.55	30.27	30.21	30.37
31	31.41	31.37	31.42	31.45
32	32.42	32.11	32.08	32.25
33	33.48	33.07	33.16	33.20
34	34.40	34.10	34.10	34.41
35	35.54	35.09	35.03	35.35
36	36.40	36.01	36.07	36.29
37	37.46	37.16	37.19	37.29
38	38.59	38.12	38.23	38.30
39	39.47	39.19	39.19	39.48
40	40.40	40.04	40.05	40.32
41	41.49	41.27	41.20	41.45
42	42.52	42.14	42.16	42.41
43	43.54	43.03	43.04	43.14
44	44.48	44.10	44.03	44.22
45	45.60	45.10	45.11	45.20
46	46.50	46.16	46.18	46.53
47	47.57	47.16	47.18	47.25
48	48.53	48.09	48.22	48.36
49	49.60	49.24	49.44	49.18
50	50.44	50.10	50.09	50.24
51	51.50	51.55	51.11	51.69
52	52.54	52.17	52.36	52.45
53	53.45	53.36	53.43	53.64
54	54.47	54.14	54.31	54.30
55	55.60	55.13	55.24	55.22
56	56.56	56.03	56.19	56.17
57	57.54	57.08	57.53	57.36
58	58.58	58.18	58.08	58.63
59	59.54	59.05	59.14	59.04
60	60.49	60.03	60.07	60.54
61	61.62	61.74	61.47	61.46
62	62.53	62.25	62.93	62.91
63	63.56	64.00	63.40	63.72
64	64.44	64.25	64.58	65.36
65	65.56	65.25	65.11	65.15
66	66.50	66.14	66.12	66.24
67	67.43	67.65	67.15	67.32
68	68.38	68.05	68.36	68.59
69	70.16	70.39	70.13	69.78
70	70.58	70.78	70.56	70.78
71	71.45	71.58	71.24	72.08
72	72.48	72.16	72.03	72.81
73	73.43	73.12	73.18	73.28
74	74.49	74.13	74.37	74.47
75	75.35	75.09	75.12	75.13
76	76.44	76.40	76.10	76.32
77	77.50	77.46	77.12	77.57
78	78.40	78.27	78.12	78.31
79	79.47	79.13	79.11	79.45
80	80.41	80.13	80.12	80.37
81	81.44	81.14	81.23	81.34
82	82.55	82.19	82.25	84.44
83	83.71	83.34	83.19	83.45
84	84.50	84.11	84.42	84.85
85	85.74	85.58	85.44	85.70
86	86.58	86.03	86.14	86.15
87	87.69	87.18	87.12	87.23
88	88.46	88.04	97.47	88.22
89	89.55	90.00	89.64	89.70
90	91.42	91.01	90.71	90.37
91	91.64	91.16	92.14	91.42
92	92.49	92.15	92.07	92.17
93	93.49	93.23	93.57	93.47
94	94.52	94.19	94.38	94.47
95	95.57	95.30	95.28	95.31
96	96.55	96.11	96.06	96.48
97	97.52	97.09	97.73	97.46
98	98.71	98.07	98.35	98.55
99	99.60	99.13	99.18	99.71
100	100.83	100.16	100.30	100.78
110	110.49	110.31	110.42	110.22
120	120.47	120.19	121.13	121.35
130	130.70	130.48	130.26	130.21
140	140.69	140.56	140.07	140.85
150	150.48	150.27	150.28	150.23
160	160.52	160.07	160.07	160.41
170	170.43	170.20	170.58	170.41
180	180.52	180.05	180.24	180.87
190	190.41	190.21	190.12	190.25
200	200.40	200.09	200.27	200.30
210	210.55	210.60	210.46	210.43
220	220.54	220.09	220.05	220.27
230	230.47	230.14	230.20	230.71
240	240.68	240.22	240.08	240.21
250	250.51	250.56	250.06	250.30
260	260.45	260.22	260.10	260.30
270	270.43	270.06	270.14	270.32
280	280.41	280.12	280.09	280.22
290	290.48	290.48	290.40	290.23
300	300.53	300.10	300.24	300.22
310	310.50	310.24	310.14	310.45
320	320.44	320.12	320.15	320.19
330	330.46	330.10	330.18	330.27
340	340.41	340.11	340.05	340.40
350	350.48	350.19	350.14	350.44
360	360.45	360.13	360.12	360.20
370	370.50	370.20	370.13	370.22
380	380.43	380.07	380.05	380.27
390	390.44	390.05	390.08	390.26
400	400.42	400.15	400.03	400.20
410	410.46	410.12	410.10	410.28
420	420.45	420.00	420.12	420.28
430	430.48	430.10	430.08	430.21
440	440.45	440.02	440.09	440.11
450	450.51	450.22	450.11	450.39
460	460.48	460.10	460.14	460.29
470	470.55	470.28	470.08	470.62
480	480.50	480.24	480.37	480.61
490	490.56	490.06	490.08	490.17
500	500.54	500.13	500.03	500.40
510	510.56	510.13	510.18	510.35
520	520.43	520.09	520.09	520.23
530	530.51	530.18	530.19	530.26
540	540.51	540.10	540.16	540.40
550	550.52	550.13	550.20	550.30
560	560.45	560.08	560.15	560.20
570	570.44	570.12	570.33	570.30
580	580.38	580.19	580.05	580.18
590	590.41	590.08	590.05	590.27
600	600.41	600.08	600.07	600.26
610	610.49	610.33	610.20	610.27
620	620.50	619.99	620.14	620.36
630	630.45	630.11	630.08	630.32
640	640.41	640.18	640.08	640.13
650	650.51	650.19	650.19	650.23
660	660.39	660.04	660.04	660.16
670	670.49	670.37	670.18	670.25
680	680.39	680.13	680.21	680.24
690	690.45	690.30	690.10	690.26
700	700.41	700.23	700.08	700.19
710	710.44	710.09	710.21	710.28
720	720.45	720.06	720.04	720.16
730	730.45	730.07	730.13	730.23
740	740.44	740.19	740.11	740.08
750	750.42	750.12	750.26	750.41
760	760.46	760.06	760.15	760.28
770	770.74	770.45	770.42	770.58
780	780.90	780.30	780.33	780.63
790	792.37	790.56	790.35	790.54
800	800.57	800.29	800.37	800.33
810	810.71	810.34	810.49	812.78
820	820.70	820.41	821.46	823.84
830	830.63	830.22	830.50	830.55
840	840.55	840.19	840.26	840.52
850	850.67	850.37	850.27	850.47
860	860.48	860.25	860.58	860.41
870	870.52	870.73	870.84	870.86
880	880.51	880.22	880.15	880.55
890	890.59	890.27	890.30	890.53
900	902.35	900.28	900.28	900.38
910	910.54	910.27	910.51	910.55
920	920.56	920.58	920.28	920.57
930	930.70	930.29	930.33	930.61
940	941.74	940.11	940.20	940.76
950	950.74	950.09	950.19	950.26
960	960.44	960.09	960.17	960.39
970	970.46	970.09	970.12	970.39
980	980.44	980.11	980.14	980.29
990	990.52	990.06	990.44	990.33
1000	1000.46	1000.03	1000.23	1000.13

结论

1. windows平台，GetTickCount、GetTickCount64、Timer三者差别不大，都是以大约15.6ms为一个梯度；Sleep相对精度更高一些。

2. linux平台，Sleep、GetTickCount、GetTickCount64、Timer四者差别都不大，但Sleep和Timer的线性（即精度）略不如GetTickCount和GetTickCount64。

精度级别	方法
1	linux平台的GetTickCount和GetTickCount64
2	两个平台的Sleep和linux平台的Timer
3	windows平台的GetTickCount、GetTickCount64、Timer