netdev - Re: O(n^2) or worse ? cat /proc/net/tcp

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	24 Mar 2008 05:06:28 +0100
From:	Andi Kleen <andi@...stfloor.org>
To:	Matti Aarnio <matti.aarnio@...iler.org>
Cc:	netdev@...r.kernel.org
Subject: Re: O(n^2) or worse ?   cat /proc/net/tcp

Matti Aarnio <matti.aarnio@...iler.org> writes:
> 
> I did observe odd slowness at first with  "lsof -p .."  program, 

You could oprofile it.

> then at
> "netstat -na".  Same slowdown happens with:  cat /proc/net/tcp
> (that 'cat' took 25 seconds...)

/proc/net/tcp should be only O(n^2) if the application does a lot of 
open()/seek()/read()/close() for very small chunks, but at least netstat
doesn't do that. Not sure about lsof though.

-Andi
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html