Re: [patch][rfc] acpi: do not use kmem caches

Alexey Starikovskiy
2008-12-01T16:45:17Z

Nick Piggin wrote:
> On Mon, Dec 01, 2008 at 05:02:50PM +0300, Alexey Starikovskiy wrote:
>
>> Because SLAB has standard memory wells of 2^x size. None of cached ACPI
>> objects has exactly this size, so bigger block will be used. Plus,
>> internal ACPICA caching will add some overhead.
>>
>
> That's an insane looking caching thing now that I come to closely read
> the code. There is so much stuff there that I thought it must have been
> doing something useful which is why I didn't replace the Linux functions
> with kmalloc/kfree directly.
>
> There is really some operating system you support that has such a poor
> allocator that you think ACPI can do better in 300 lines of code? Why
> not just rip that whole thing out?
>
You would laugh, this is due to Windows userspace debug library -- it
checks for
memory leaks by default, and it takes ages to do this.
And ACPICA maintainer is sitting on Windows, so he _cares_.
>> Do you have another interpreter in kernel space?
>>
>
> So what makes it special?
>
>
You don't know what size of program you will end up with.
DSDT could be almost empty, or you could have several thousand of SSDT
tables.