What Alexey's code does is _not_ preallocation -- it does re-cycling.
On tx_completion, the skb is recycled onto a recycle queue unless the
queue is full (which is a tunable parameter) in which case it is freed.
This is more sensible than doing pre-allocation during idle times
or other smart schemes. On a busy system this queue will always
have something.
What i meant by aging is to have a separate thread that prunes the queue
based on age i.e how long the skb has been sitting there etc. I think Jes
had a bottom-half running there; a simple per-cpu timer might suffice.
The heuristic (such as the timer decay etc) for this part needs a study
and thats what Robert and i are planing to do.
cheers,
jamal
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