From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg KH Date: Sat, 07 Feb 2004 19:31:37 +0000 Subject: Re: [RFC] reliability and scalability Message-Id: <20040207193137.GC5003@kroah.com> List-Id: References: <40249B59.7080805@sympatico.ca> In-Reply-To: <40249B59.7080805@sympatico.ca> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-hotplug@vger.kernel.org On Sat, Feb 07, 2004 at 03:01:29AM -0500, Chris Friesen wrote: > > I've got a couple more ideas for improving udevd, but before I go crazy > with this I wanted to get some opinions from people more experienced > than me. > > First, how paranoid should we be about reliability? Right now there is a > (low) possibility of udevd crashing with unhandled messages on its rx > buffer, thus losing one or more hotplug events. Is this a problem? > Would people welcome a patch that closes the loop by sending an ack back > to udevsend? I would welcome this. We really don't want to loose events. But how long should udevsend wait before retrying the message? I can see this getting messy... > Second, how many udev instances are we expecting to have outstanding at > a time? As many as possible? :) > There are a couple of places in udevd (specifically the devpath > check and the udev_done code) that with the current data structures end > up being worst case ofO(n^2). Is this a problem? The average user will > never have an issue, but if we suddenly plug in a few thousand disks (a > number that's been mentioned before), is it a big deal if it takes a > bit longer to add them all? I see ways of getting around this, but > it may be overkill. This is very easy to test with scsi-debug. I don't really think this is a issue right now, but if you want to try improving it a bit, please do. thanks, greg k-h ------------------------------------------------------- The SF.Net email is sponsored by EclipseCon 2004 Premiere Conference on Open Tools Development and Integration See the breadth of Eclipse activity. February 3-5 in Anaheim, CA. http://www.eclipsecon.org/osdn _______________________________________________ Linux-hotplug-devel mailing list http://linux-hotplug.sourceforge.net Linux-hotplug-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel