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]
Message-ID: <MDEHLPKNGKAHNMBLJOLKGEAJDEAC.davids@webmaster.com>
Date:	Mon, 23 Apr 2007 15:52:58 -0700
From:	"David Schwartz" <davids@...master.com>
To:	<linux-kernel@...r.kernel.org>
Subject: RE: sendfile to nonblocking socket


> As I see, nonblocking mode is enabled - sendfile sends less than asked.  
> But 2G via single 30 seconds sendfile call - this is blocking call. How 
> can I  avoid that?  I prefer sendfile as fastest way to send file 
> content to network socket. The problem with sendfile block on 
> nonblocking socket has place only when I'm using network connection, 
> that is faster than my hard disk, for example  gigabit NIC or localhost. 
> When I use 100Mbit NIC, which is slower, than my hard disk,  I got small 
> and fast sendfile calls without blocking.
> 
> My kernel is  Linux 2.6.20.3-grsec x86_64. I verified that also on 
> 2.6.18 - same results. Please advise.

You have a misunderstanding about the semantics of 'sendfile'. The 'sendfile' function is just a more efficient version of a read followed by a write. If you did a read followed by a write, it would block as well (in the read).

DS


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ