Messages in this thread | | | Subject | Re: [PATCH][RFC][BUG] updating the ctime and mtime time stamps in msync() | From | Valdis.Kletnieks@vt ... | Date | Wed, 09 Jan 2008 16:06:17 -0500 |
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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] | |