From: Wendy Cheng Subject: Re: multiple instances of rpc.statd Date: Fri, 25 Apr 2008 11:39:15 -0400 Message-ID: <4811FB23.4010509@gmail.com> References: <200804251531.21035.bs@q-leap.de> <4811E0D7.4070608@gmail.com> <200804251630.36917.bs@q-leap.de> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15; format=flowed Cc: linux-nfs@vger.kernel.org To: Bernd Schubert Return-path: Received: from mx2.netapp.com ([216.240.18.37]:58633 "EHLO mx2.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754423AbYDYPhW (ORCPT ); Fri, 25 Apr 2008 11:37:22 -0400 In-Reply-To: <200804251630.36917.bs-PKu+Ek1N2UGzQB+pC5nmwQ@public.gmane.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: Bernd Schubert wrote: > Hello Wendy. > > On Friday 25 April 2008 15:47:03 Wendy Cheng wrote: > >> The efforts have been attempted (to remedy this issue) and a complete >> set of patches have been (kept) submitting for the past two years. The >> patch acceptance progress is very slow (I guess people just don't want >> to get bothered with cluster issues ?). >> > > Well, I think people are just ignorant. I did see your discussions about NLM > in the past on the NFS mailing list, but actually I didn't understand the > entire point of discussion ;) I was simply used to active-passive services > (mostly due to heartbeat-1.x) and there we just had /var/lib/nfs linked to > the exported directory. > > After I started to work here, I was confronted with the fact we do have > working active-active clusters here, but nobody besides me ever cared about > the locking problem :( NFS failovers just are done ignoring file locks. > Seems so far also nobody run into a problem, but maybe the result was so > obscure that nobody ever bothered to complain... > I'm just afraid most admins will simply do like this... > That's an accurate observation :) .. people are just ignorant until they get bitten by the problem. Then they blush out nasty words about Linux servers and go for proprietary solutions. There are amazing amount of "workaround"(s) and funny setup(s) to bypass various Linux problems. Admins normally don't care the details but just know if they do certain "tricks", things work. I was looking at a performance issue last week why clustered mail servers ran miserably slow. As a person who don't know much about mail server, I was surprised to learn it is a common practice that linux email servers could be configured to grab flock, followed by posix lock, then wrote a lock file whenever a "write" occurs - all three actions are used concurrently to protect one single file (?). It was a very interesting conversation. -- Wendy