Re: POSIX violation by writeback error

焦晓冬
2018-09-04T10:46:08Z

On Tue, Sep 4, 2018 at 5:29 PM Rogier Wolff <R.E.Wolff@bitwizard.nl> wrote:
>
> On Tue, Sep 04, 2018 at 04:58:59PM +0800, 焦晓冬 wrote:
>
> > As for suggestion, maybe the error flag of inode/mapping, or the entire inode
> > should not be evicted if there was an error. That hopefully won't take much
> > memory. On extreme conditions, where too much error inode requires staying
> > in memory, maybe we should panic rather then spread the error.
>
> Again you are hoping it will fit in memory. In an extreme case it
> won't fit in memory. Tyring to come up with heuristics about when to
> remember and when to forget such things from the past is very
> difficult.

The key point is to report errors, not to hide it from user space to
prevent further errors/damage,
and that is also what POSIX wants.

And, storing inode/mapping/error_flag in memory is quite different
from storing the data itself.
They are tiny and only increase per inode rather than per error page.
>
> Think of my comments as: "it's harder than you think", not as "can't
> be done".
>
> Roger.
>
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