Re: [Kiobuf-io-devel] RFC: Kernel mechanism: Compound event wait

Ingo Molnar
2001-02-06T09:32:12Z

On Mon, 5 Feb 2001, Linus Torvalds wrote:

> [...] But talk to Davem and ank about why they wanted vectors.

one issue is allocation overhead. The fragment array is a natural and
constant-size part of an skb, thus we get all the control structures in
place while allocating a structure that we have to allocate anyway.

another issue is that certain cards have (or can have) SG-limits, so we
have to be prepared to have a 'limited' array of fragments anyway, and
have to be prepared to split/refragment packets. Whether there is a global
MAX_SKB_FRAGS limit or not makes no difference.

Ingo