[dm-devel] Re: How to handle >16TB devices on 32 bit hosts ??

[Pavel Machek <pavel ucw cz>]

Hi!

> > > Also, for filesystems like btrfs or ZFS the checking can be done
> > > online and incrementally without storing a full representation of
> > > the state in memory.
> > 
> > You could, but I suspect it would be cheaper to just use a
> > 64bit system than to rewrite fsck. 64bit is available
> > for a lot of embedded setups these days too.
> 
> We don't have to rewrite fsck; most of the framework for supporting an
> run-length-conding for compressed bitmaps is already in patches that
> add > 32-bit block numbers to e2fsprogs; we've just been more focused
> on getting 64-bit block numbers support merged than implementing
> compressed bitmaps, but it's only one file that would need to be
> added, and we might be able to steal the compressed bitmap support
> from xfsprogs --- which does this already.

Well... 'If allocation pattern is bad your fsck runs out of address
space and breaks on your 15T fs' would scare me.

-- 
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