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Metadata for Your Data

ctime-mtime Difference Statistics

The next set of statistics are for the difference between ctime and mtime., which can tell you the metadata changes (ctime) versus data changes (mtime). In the following analysis, the difference between the two (ctime/mtime) are used.

  • Average ctime/mtime: 700.000 days
  • Oldest ctime/mtime file: 5,153.000 days
  • Youngest ctime/mtime file: 0.000 days
  • Standard deviation ctime/mtime: 543.8009 days

Table 5:ctime/mtime Age Intervals

Interval (days) No. of files % of Total Cumulative %
0–1 53,756 13.85 13.85
1–2 73 0.02 13.87
2–4 121 0.03 13.90
4–7 168 0.04 13.94
7–14 1,111 0.29 14.2
14–28 8,768 2.26 16.49
28–56 25,377 6.54 23.03
56–112 8,101 2.09 25.12
112–168 47,729 12.30 37.42
168–252 3,578 0.92 38.34
252–365 4,970 1.28 39.62
365–504 2,324 0.60 40.22
504–730 3,270 0.84 41.06
730–1,095 37,909 9.77 50.83
1,095–1,460 189,729 48.89 99.72
1,460–1,825 254 0.07 99.78
1,825–2,190 255 0.07 99.85
2,190–2,920 324 0.08 99.93
2,920–3,650 136 0.04 99.97
3,650–4,380 3 0.00 99.97
4,380–5,110 122 0.03 100.00
5,110–5,840 5 0.00 100.00

Table 6 lists the top 10 files with the largest ctime/mtime differences.

Table 6: Top 10 Oldest Files Based on ctime/mtime

Rank File xtime /mtime  Difference (days)
1 /home/laytonjb/.gkrellm2/themes/x17/bg_grid.png 5,153.421
2 /home/laytonjb/.gkrellm2/themes/brushed/bg_grid.png 5,153.420
3 /home/laytonjb/.gkrellm2/themes/brushed/bg_chart.png 5,153.420
4 /home/laytonjb/.gkrellm2/themes/brushed/d 5,153.420
5 /home/laytonjb/.gkrellm2/themes/brushed/gismrc~ 5,153.420
6 /home/laytonjb/.gkrellm2/themes/brushed/gkrellmrc 4,986.920
7 /home/laytonjb/.gkrellm2/themes/x17/host/bg_panel.png 4,985.801
8 /home/laytonjb/.gkrellm2/themes/x17/net/decal_net_leds.png 4,985.801
9 /home/laytonjb/.gkrellm2/themes/x17/frame_left.png 4,985.801
10 /home/laytonjb/.gkrellm2/themes/x17/frame_bottom.png 4,985.801

Figure 3 is a histogram of the ctime/mtime differences of the files in the pickle.

Figure 3: Ctime/mtime histogram.
Atime Age Statistics

Atime is the change time of the file. It will change only if the actual data is changed, but not if the metadata is changed.

  • Average atime age: 128.273 days
  • Oldest atime: 2,030.272 days
  • Youngest atime: 0.307 days
  • Standard deviation atime: 98.5828 days

Table 7 lists the atime age intervals. The age is based on the atime of the files when scanned and the current time.

Table 7: Atime Age Intervals

Interval (days) No. of Files % of Total Cumulative %
0–1 406 0.10 0.10
1–2 0 0.00 0.10
2–4 396 0.10 0.21
4–7 4,710 1.21 1.42
7–14 60 0.02 1.44
14–28 16,108 4.15 5.59
28–56 7,987 2.06 7.64
56–112 19,803 5.10 12.75
112–168 334,034 86.07 98.82
168–252 1,288 0.33 99.15
252–365 425 0.11 99.26
365–504 923 0.24 99.50
504–730 25 0.01 99.51
730–1,095 78 0.02 99.53
1,095–1,460 1,831 0.47 100.00
1,460–1,825 0 0.00 100.00
1,825–2,190 9 0.00 100.00
2,190–2,920 0 0.00 100.00
2,920–3,650 0 0.00 100.00
3,650–4,380 0 0.00 100.00
4,380–5,110 0 0.00 100.00
5,110–5,840 0 0.00 100.00

Table 8 lists the top 10 files based on atime (access time) when the files were scanned in the original pickle file.

Table 8: Top 10 Oldest Files Based on atime

Rank File atime Age
1 /home/laytonjb/CLUSTERBUFFER/STRACE/DB/DBIx-SimplePerl-1.90/blib/script/.exists 2,030.271
2 /home/laytonjb/CLUSTERBUFFER/STRACE/DB/DBIx-SimplePerl-1.90/blib/man3/.exists 2,030.271
3 /home/laytonjb/CLUSTERBUFFER/STRACE/DB/DBIx-SimplePerl-1.90/blib/lib/auto/DBIx/SimplePerl/.exists 2,030.271
4 /home/laytonjb/CLUSTERBUFFER/STRACE/DB/DBIx-SimplePerl-1.90/blib/lib/DBIx/.exists 2,030.271
5 /home/laytonjb/CLUSTERBUFFER/STRACE/DB/DBIx-SimplePerl-1.90/blib/bin/.exists 2,030.271
6 /home/laytonjb/CLUSTERBUFFER/STRACE/DB/DBIx-SimplePerl-1.90/blib/arch/auto/DBIx/SimplePerl/.exists 2,030.271
7 /home/laytonjb/CLUSTERBUFFER/STRACE/DB/DBIx-SimplePerl-1.90/blib/arch/.exists 2,030.271
8 /home/laytonjb/CLUSTERBUFFER/STRACE/DB/DBIx-SimplePerl-1.90/blib/man1/.exists 2,030.271
9 /home/laytonjb/CLUSTERBUFFER/STRACE/DB/DBIx-SimplePerl-1.90/pm_to_blib 2,030.271
10 /home/laytonjb/src/CFD/CFD_2/USM3D/USM3D_DATA/RAMP/ramp1.m2 1,441.099


Figure 4: Atime histogram.

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