Messages in this thread | | | Date | Tue, 23 Jun 2009 20:29:41 +0200 | From | Pavel Machek <> | Subject | Re: [PATCH 00/14] Pramfs: Persistent and protected ram filesystem |
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On Tue 2009-06-23 20:07:23, Marco wrote: > Pavel Machek wrote: > > On Mon 2009-06-22 14:50:01, Tim Bird wrote: > >> Pavel Machek wrote: > >>>> block of fast non-volatile RAM that need to access data on it using a > >>>> standard filesytem interface." > >>> Turns a block of fast RAM into 13MB/sec disk. Hmm. I believe you are > >>> better with ext2. > >> Not if you want the RAM-based filesystem to persist over a kernel > >> invocation. > > > > Yes, you'll need to code Persistent, RAM-based _block_device_. > > First of all I have to say that I'd like to update the site and make it > clearer but at the moment it's not possible because I'm not the admin > and I've already asked to the sourceforge support to have this possibility. > > About the comments: sincerely I don't understand the comments. We have > *already* a fs that takes care to remap a piace of ram (ram, sram, > nvram, etc.), takes care of caching problems, takes care of write
Well, it looks pramfs design is confused. 13MB/sec shows that caching _is_ useful for pramfs. So...?
> You are talked about journaling. This schema works well for a disk, but > what about a piece of ram? What about a crazy kernel that write in that > area for a bug? Do you remember for example the e1000e bug? It's not
I believe you need both journaling *and* write protection. How do you handle power fault while writing data? Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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