Re: Swap support

Riley Williams
2002-04-22T20:35:48Z

Hi Harry.

>> Would you mind if I tweaked the config system to allow this to be
>> configured therein, making the entire configuration dependent on
>> the CONFIG_EXPERIMENTAL config variable?

> Yes make it dependent on CONFIG_EXPERIMENTAL, as for the
> configuration of the swap partition leave it as it is now,
> since it is only for developers at the moment...

No problem. There's two thing that strike me though:

1. Does it actually make sense to use a ramdisk as a swap drive?

2. If we're using a hard drive partition as a swap partition,
doesn't the kernel already know the size of that partition?

If (2) is true, then the extents field is not one needing configuration
anyway as we can just grab the value the kernel has already determined
earlier in the boot process. At least, I hope it has, as it doesn't make
sense for the swap code to be enabled prior to our autoprobing for the
hard drive partition sizes.

>> Also, does it use any particular format for the swap partition?

> There is no need to format the block device (partition) to be used...

True, but it misses what I was asking. Basically, are we emulating the
Linux swap code in this respect, in that we store a swap signature at
the start of the swap partition, or are we just using the partition raw?

>> I'm presuming from the above that it operates at partition level
>> rather than at device level, so doesn't require a separate hard
>> drive for swap usage.

This comment was because your previous phraseology implied that we used
[say] /dev/edb as the swap device, but I suspect we're more likely to be
using [say] /dev/edb1 instead.

Best wishes from Riley.