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From: Jerry Chu <hkchu@google.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Stephen Hemminger <shemminger@vyatta.com>, netdev@vger.kernel.org
Subject: Re: [PATCH] Add useful per-connection TCP stats for diagnosis purpose.
Date: Fri, 18 Mar 2011 22:38:52 -0700	[thread overview]
Message-ID: <AANLkTimsoF+khCfU2aEQNoJ0DBf_p9-v+Zim0X5RrLpw@mail.gmail.com> (raw)
In-Reply-To: <1300510960.2831.2.camel@edumazet-laptop>

On Fri, Mar 18, 2011 at 10:02 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> Le vendredi 18 mars 2011 à 21:33 -0700, Jerry Chu a écrit :
>
>> I'm well aware of the past, hideous O(n**2) problem of reading
>> /proc/net/tcp but I
>> thought the problem has been fixed by Tom Herbert a while back, no?
>> (See http://marc.info/?l=linux-netdev&m=127588123429437&w=2)
>>
>
> O(N) is still too slow, to gather stats for your socket, if you want to
> gather stats once per second for example.

I don't see anyway around O(n). The netlink/inet_diag_dump() will take at
best O(n) too.

>
> AFAIK, I am not sure we want to allow any user to access all these data
> for all tcp sockets on the machine. This might have security impacts.

This seems to be an orthogonal issue to netlink or /proc/net/tcp.

Jerry

>
>
>
>

  reply	other threads:[~2011-03-19  5:38 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-03-17  8:06 [PATCH] Add useful per-connection TCP stats for diagnosis purpose H.K. Jerry Chu
2011-03-17  8:42 ` Eric Dumazet
2011-03-17 20:16   ` Jerry Chu
2011-03-17 21:20     ` Stephen Hemminger
2011-03-18  4:33       ` Jerry Chu
2011-03-18  4:51         ` David Miller
2011-03-18  6:05         ` Eric Dumazet
2011-03-19  4:33           ` Jerry Chu
2011-03-19  5:02             ` Eric Dumazet
2011-03-19  5:38               ` Jerry Chu [this message]
2011-03-19  6:03                 ` Eric Dumazet
2011-03-20  7:30                   ` Jerry Chu
2011-03-20  9:18                     ` Eric Dumazet
2011-03-21 21:18             ` Stephen Hemminger
2011-03-21 22:19               ` Ben Greear

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