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    SubjectRe: [PATCH v5 2/2] netfilter: save the hash of the tuple in the original direction for latter use
    On 20.09.2010 17:04, Changli Gao wrote:
    > On Thu, Sep 16, 2010 at 2:18 PM, Patrick McHardy <> wrote:
    >> On 21.08.2010 00:49, Changli Gao wrote:
    >>> Since we don't change the tuple in the original direction, we can save it
    >>> in ct->tuplehash[IP_CT_DIR_REPLY].hnode.pprev for __nf_conntrack_confirm()
    >>> use.
    >> I like this idea. We could actually do the same for the reply tuple
    >> and invalidate the saved hash in case the reply tuple is changed
    >> (nf_conntrack_alter_reply()), which only happens when NAT is used.
    > We can't do that, as the unconfirmed ct owned maybe dropped, and
    > pre-computing will wast CPU cycles in this case.

    Sure we can, dropping unconfirmed conntracks is a rare exception,
    not a common case. Even under DoS we usually drop *unassured*
    conntracks, which have already enterered the hash. If we're unable
    to do that, we won't even allocate a new conntrack.

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      Last update: 2010-09-20 19:11    [W:0.042 / U:9.532 seconds]
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