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    SubjectRe: [PATCH 2.6.21-rc6] [netfilter] early_drop imrovement
    Vasily Averin wrote:
    > No, I've not investigated this scenario. It looks like you are right and my
    > patch can leads to a long delays.
    >
    > In my experiments I've decreased ip_conntrack_max lower than number of hash
    > buckets and got the "table full, dropping packet" errors in logs. I've looked on
    > the conntrack list and found a huge number of conntracks that can be freed.
    > However my hash bucket was empty and therefore I even did not have any chances
    > to free something. That's why I would like to check the other hash buckets too.
    >
    > Ok, let's limit the number of conntracks that can be checked inside
    > early_drop(). What do you prefer: some round number (for example 100) or
    > fraction of ip_conntrack_max (for example 1%)?


    A (small) fraction sounds better. We could even consider keeping track
    of the number of conntracks that can be evicted (not assured), so in a
    DOS situation we could save unnecessary table scans. Not sure if its
    worth the effort though.

    Anyway, please base your patch on the net-2.6.22 tree, which doesn't
    include ip_conntrack anymore.

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