Messages in this thread | | | Date | Mon, 17 May 2004 07:52:17 -0700 | From | Larry McVoy <> | Subject | Re: 1352 NUL bytes at the end of a page? (was Re: Assertion `s && s->tree' failed: The saga continues.) |
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On Mon, May 17, 2004 at 07:32:44AM -0700, Linus Torvalds wrote: > My claim (which may be bogus, but isn't), is that you wrote the file with > a buffered interface like stdio (or your own buffers), and that the buffer > size is likely a nice round number like 8kB or something. I think that's > what stdio uses by default.
Yup, that's what we do.
> And at some point earlier in the process you did an fflush(), or somebody > else had written a header of n*PAGE_SIZE + 0x4ff bytes, or something like > that. Since this was the ChangeSet file, I suspect that the "header" is > the checkin-comment section at the beginning, and the "second phase" is > the actual key list thing. You know how you write the ChangeSet file > better than I do.
I don't think we flush along the way but let me look. Whoops, you're right, we do. Right where you thought too. But that doesn't explain there being 3 blocks of nulls (there should NEVER be a null in the s.ChangeSet file, we don't compress that, it's always ascii).
But the bigger problem is that you are missing the point that I mentioned elsewhere, we are writing to a tmp file, the tmp file is NOT mmapped. We mmap only after that file is closed and renamed. We don't map the tmp file. -- --- Larry McVoy lm at bitmover.com http://www.bitkeeper.com - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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