From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yann Droneaud Subject: Re: rdma_connect() "timeout" Date: Wed, 18 Jul 2012 19:16:06 +0200 Message-ID: <1342631766.19395.48.camel@test.quest-ce.net> References: <1342624372.19395.35.camel@test.quest-ce.net> <1828884A29C6694DAF28B7E6B8A8237346A6A5AA@ORSMSX101.amr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1828884A29C6694DAF28B7E6B8A8237346A6A5AA-P5GAC/sN6hmkrb+BlOpmy7fspsVTdybXVpNB7YpNyf8@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: "Hefty, Sean" Cc: "linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , ydroneaud-RlY5vtjFyJ3QT0dZR+AlfA@public.gmane.org List-Id: linux-rdma@vger.kernel.org Hi, Le mercredi 18 juillet 2012 =C3=A0 15:49 +0000, Hefty, Sean a =C3=A9cri= t : > > Is there a way to setup the timeout in rdma_connect() ? >=20 > For IB, the timeout is based on the packet lifetime in the path recor= d returned by the SA. =20 > The rdma_cm will retry a CM REQ the maximum number of times (15). > =20 According to the OpenSM default configuration (/usr/sbin/opensm --create-config ) : # The subnet_timeout code that will be set for all the ports # The actual timeout is 4.096usec * 2^ subnet_timeout 18 # The code of maximal time a packet can live in a switch # The actual time is 4.096usec * 2^ # The value 0x14 disables this mechanism packet_life_time 0x12 Despite the notation, they are the same values. It gives me: 4.096 * 10^-6 * 2^18 =3D 1.074 s 15 * subnet timeout / packet life time =3D 16.106 s ...=20 This is a lot less than 98 s. Where does come the difference ? > > Is there a way to change the CM parameters ? e.g. "Service Timeout"= to > > wait for moving from "REP wait" state to "Timeout" state, and the n= umber > > of send "REQ" retries (From 12.9.5 "Communication Establishement an= d > > Release - Active") ? >=20 > There is no direct way to change the timeout parameter. You would ne= ed to adjust the subnet timeout values at the SA. Is it subnet_timeout or packet_life_time ? Thanks for your answers. Regards. --=20 Yann Droneaud OPTEYA -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" i= n the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html