2005-01-23 17:01:59

by Maciej Sołtysiak

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Subject: Support for Large Block Devices

Hi,

I was wondering... Why is "Support for Large Block Devices"
still an option?

Shouldn't it be compiled in always?
Or maybe there are some cons like incompatibility or something?

Regards,
Maciej



2005-01-24 23:53:48

by Peter Chubb

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Subject: Re: Support for Large Block Devices

>>>>> "Maciej" == Maciej Soltysiak <[email protected]> writes:

Maciej> Hi, I was wondering... Why is "Support for Large Block
Maciej> Devices" still an option?

Maciej> Shouldn't it be compiled in always? Or maybe there are some
Maciej> cons like incompatibility or something?

It's not compiled in always on 32-bit platforms, because
1. Most people don't have more than 2TB in a single block device
2. 64-bit sizes mean increased size of various structures (i.e.,
less cache-friendly), and slightly slower operations.

On 64-bit platforms it *is* always enabled.
--
Dr Peter Chubb http://www.gelato.unsw.edu.au peterc AT gelato.unsw.edu.au
The technical we do immediately, the political takes *forever*