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
| ||
|
Date: Fri, 5 Sep 2008 13:28:03 +0300 From: "Robert Iakobashvili" <coroberti@...il.com> To: "Johann Baudy" <johaahn@...il.com> Cc: netdev@...r.kernel.org, "Ulisses Alonso CamarĂ³" <uaca@...mni.uv.es> Subject: Re: Packet mmap: TX RING and zero copy Hi Johann, On Tue, Sep 2, 2008 at 9:27 PM, Johann Baudy <johaahn@...il.com> wrote: > I've made lot of tests, playing with jumbo frames, raw sockets, ... > I've never exceeded ~25Mbytes/s. So I've decided to analyze deeply the > packet socket transmission process. > > The main blocking point was the memcpy_fromiovec() function that is > located in the packet_sendmsg() of af_packet.c. > It was consuming all my CPU resources to copy data from user space to > socket buffer. > Then I've started to work on a hack that makes this transfer possible > without any memcpys. > > Mainly, the hack is the implementation of two "features": > > * Sending packet through a circular buffer between user and > kernel space that minimizes the number of system calls. (Feature > actually implemented for capture process, libpcap ..). Something like this has been done in PF_RING socket, which is a part of ntop project infra. Take care. Truly, Robert Iakobashvili ...................................................................... www.ghotit.com Assistive technology that understands you ...................................................................... -- 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
Powered by blists - more mailing lists