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At Sun, 01 Mar 2009 13:57:30 +0200 Nikos Chantziaras <realnc@×××××.de> wrote: |
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> Peter Humphrey wrote: |
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>> As it's Sunday, here's an odd little thing. |
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>> |
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>> Not long ago, while booting this machine, four ext3 partitions |
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>> needed checks on remount count reaching zero. They had been set to |
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>> 23, 24, 25 and 26 mounts. (I didn't choose the numbers; they were |
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>> allocated at the time I was creating the file system.) |
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>> |
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>> Now, this box does get rebooted, but hardly 23 x 24 x 25 x 26 = |
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>> 358,800 times all told. At, say, two reboots per day, that would |
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>> take rather a long time: a little under 500 years if my arithmetic |
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>> is working. |
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> |
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> I think you're confused. 23 means a check each 23 mounts. With 2 |
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> mounts per day, that's a check every 12 days for the first and second |
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> disk. |
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I think the point is that 23, 24, 25, 26 are relatively prime so that, |
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if N is initially zero, it takes 23x24x25x26 increments initially for (N |
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mod 23), ..., (N mod 26) to all again be zero. |
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> Also, except mount count, there's also a time-based check. The check |
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> happens whichever of the two expires first (otherwise, a system that |
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> gets rebooted once each two months or such would get checked in a |
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> timely manner.) |
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This second point is quite valid. |
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allan |
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