Re: [RFC PATCH 0/4] Add support for LZ4-compressed kernels

From: Russell King - ARM Linux
Date: Tue Jan 29 2013 - 05:17:14 EST


On Mon, Jan 28, 2013 at 02:25:10PM -0800, Andrew Morton wrote:
> What's this "with enabled unaligned memory access" thing? You mean "if
> the arch supports CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS"? If so,
> that's only x86, which isn't really in the target market for this
> patch, yes?
>
> It's a lot of code for a 50ms boot-time improvement. Does anyone have
> any opinions on whether or not the benefits are worth the cost?

Well... when I saw this my immediate reaction was "oh no, yet another
decompressor for the kernel". We have five of these things already.
Do we really need a sixth?

My feeling is that we should have:
- one decompressor which is the fastest
- one decompressor for the highest compression ratio
- one popular decompressor (eg conventional gzip)

And if we have a replacement one for one of these, then it should do
exactly that: replace it. I realise that various architectures will
behave differently, so we should really be looking at numbers across
several arches.

Otherwise, where do we stop adding new ones? After we have 6 of these
(which is after this one). After 12? After the 20th?
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/