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SubjectRe: [PATCH][RFC][BUG] updating the ctime and mtime time stamps in msync()
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On Wed, 09 Jan 2008 15:50:15 EST, Rik van Riel said:

> Could you explain (using short words and simple sentences) what the
> exact problem is?
>
> Eg.
>
> 1) program mmaps file
> 2) program writes to mmaped area
> 3) ??? <=== this part, in equally simple words :)
> 4) data loss

It's like this:

Monday 9:04AM: System boots, database server starts up, mmaps file
Monday 9:06AM: Database server writes to mmap area, updates mtime/ctime
Monday <many times> Database server writes to mmap area, no further update..
Monday 11:45PM: Backup sees "file modified 9:06AM, let's back it up"
Tuesday 9:00AM-5:00PM: Database server touches it another 5,398 times, no mtime
Tuesday 11:45PM: Backup sees "file modified back on Monday, we backed this up..
Wed 9:00AM-5:00PM: More updates, more not touching the mtime
Wed 11:45PM: *yawn* It hasn't been touched in 2 days, no sense in backing it up..

Lather, rinse, repeat....[unhandled content-type:application/pgp-signature]
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