From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bill Davidsen Subject: Re: [[Patch mdadm] 2/5] Move the files mdmon opens into /dev/ to support handoff after pivotroot Date: Mon, 01 Feb 2010 17:42:15 -0500 Message-ID: <4B6758C7.9060301@tmr.com> References: <1263242294-5353-1-git-send-email-dledford@redhat.com> <1263242294-5353-3-git-send-email-dledford@redhat.com> <20100119110930.107ca42e@notabene> <4B55F138.7060008@redhat.com> <4B673A5D.2010901@tmr.com> <4B674860.7080604@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4B674860.7080604@redhat.com> Sender: linux-raid-owner@vger.kernel.org To: Doug Ledford Cc: Neil Brown , linux-raid@vger.kernel.org List-Id: linux-raid.ids Doug Ledford wrote: > On 02/01/2010 03:32 PM, Bill Davidsen wrote: > >> Doug Ledford wrote: >> >>> On 01/18/2010 05:09 PM, Neil Brown wrote: >>> >>> >>>> I understand there is a problem here, but I don't like this approach >>>> to a >>>> solution. I'll give it more though when I get home from LCA2010 and see >>>> what I can come up with. >>>> >>>> >>> Feel free to come up with something different. But, if your solution >>> involves maintaining an additional read/write mount area in deference to >>> a long dead unix tradition, I'm just going to shake my head and patch >>> your solution away to something sane. >>> >>> >>> >> I don't understand you argument here. Not the one where you say you're >> going to ignore Neil and do what you want because you can, I understand >> that, but the "additional read/write mount area" part, isn't /var/run >> r/w on all systems now? Could you clarify why this is "additional" here? >> >> > > It's not necessarily read/write in the initrd time frame, and putting > the mdadm files there means it would have to be. We didn't make these > changes because we wanted to, we made them because using mdadm raid > arrays for the root filesystem combined with incremental assembly or > with imsm raid devices was broken otherwise. > > Do understand that my disquiet related to this isn't because you put a non-device in /dev, it's that you didn't put a process PID in /var/run. And frankly, once you let (force) one group of threads to be somewhere else, other services will want their PIDs some other place, and anyone maintaining an application which presents information on what's running will need to know where that information. In other words, it's not where you put it, it's where you *didn't* put it, that seems to be an invitation to put stuff just anywhere. Neil argues that they are not devices, I argue that they are PIDs. It's not as though it were a huge effort to move it after pivot root, it's a little code or script and in space which will be released. -- Bill Davidsen "We can't solve today's problems by using the same thinking we used in creating them." - Einstein