freebsd with flexible iflib nic queues
9c9906e912
to either enqueue or free their mbuf chains, but tcp_usr_send() was dropping them on the floor if the tcpcb/inpcb has been torn down in the middle of a send/write attempt. This has been responsible for a wide variety of mbuf leak patterns, ranging from slow gradual leakage to rather rapid exhaustion. This has been a problem since before 2.2 was branched and appears to have been fixed in rev 1.16 and lost in 1.23/1.28. Thanks to Jayanth Vijayaraghavan <jayanth@yahoo-inc.com> for checking (extensively) into this on a live production 2.2.x system and that it was the actual cause of the leak and looks like it fixes it. The machine in question was loosing (from memory) about 150 mbufs per hour under load and a change similar to this stopped it. (Don't blame Jayanth for this patch though) An alternative approach to this would be to recheck SS_CANTSENDMORE etc inside the splnet() right before calling pru_send() after all the potential sleeps, interrupts and delays have happened. However, this would mean exposing knowledge of the tcp stack's reset handling and removal of the pcb to the generic code. There are other things that call pru_send() directly though. Problem originally noted by: John Plevyak <jplevyak@inktomi.com> |
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| bin | ||
| contrib | ||
| crypto | ||
| etc | ||
| games | ||
| gnu | ||
| include | ||
| kerberos5 | ||
| kerberosIV | ||
| lib | ||
| libexec | ||
| release | ||
| sbin | ||
| secure | ||
| share | ||
| sys | ||
| tools | ||
| usr.bin | ||
| usr.sbin | ||
| COPYRIGHT | ||
| Makefile | ||
| Makefile.inc0 | ||
| Makefile.inc1 | ||
| Makefile.upgrade | ||
| README | ||
| UPDATING | ||
This is the top level of the FreeBSD source directory. This file was last revised on: $Id: README,v 1.13 1998/09/13 09:38:34 markm Exp $ For copyright information, please see the file COPYRIGHT in this directory (additional copyright information also exists for some sources in this tree - please see the specific source directories for more information). The Makefile in this directory supports a number of targets for building components (or all) of the FreeBSD source tree, the most commonly used one being ``world'', which rebuilds and installs everything in the FreeBSD system from the source tree except the kernel and the contents of /etc. Please see the top of the Makefile in this directory for more information on the standard build targets and compile-time flags. Building a kernel with config(8) is a somewhat more involved process, documentation for which can be found at: http://www.freebsd.org/handbook/kernelconfig.html And in the config(8) man page. The sample kernel configuration files reside in the sys/i386/conf sub-directory (assuming that you've installed the kernel sources), the file named GENERIC being the one used to build your initial installation kernel. The file LINT contains entries for all possible devices, not just those commonly used, and is meant more as a general reference than an actual kernel configuration file (a kernel built from it wouldn't even run). Source Roadmap: --------------- bin System/User commands. contrib Packages contributed by 3rd parties. crypto Export controlled stuff (see crypto/README). etc Template files for /etc games Amusements. gnu Various commands and libraries under the GNU Public License. Please see gnu/COPYING* for more information. include System include files. kerberosIV Kerberos package. lib System libraries. libexec System daemons. release Release building Makefile & associated tools. sbin System commands. secure DES and DES-related utilities - NOT FOR EXPORT! share Shared resources. sys Kernel sources. tools Utilities for regression testing and miscellaneous tasks. usr.bin User commands. usr.sbin System administration commands. For information on synchronizing your source tree with one or more of the FreeBSD Project's development branches, please see: http://www.freebsd.org/handbook/synching.html