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From: Pavel Machek <pavel@ucw.cz>
To: Marco Stornelli <marco.stornelli@gmail.com>
Cc: Jamie Lokier <jamie@shareable.org>,
	Linux Embedded <linux-embedded@vger.kernel.org>,
	Linux Kernel <linux-kernel@vger.kernel.org>,
	Linux FS Devel <linux-fsdevel@vger.kernel.org>,
	Daniel Walker <dwalker@soe.ucsc.edu>
Subject: Re: [PATCH 00/14] Pramfs: Persistent and protected ram filesystem
Date: Mon, 22 Jun 2009 19:20:04 +0200	[thread overview]
Message-ID: <20090622172003.GB21149@elf.ucw.cz> (raw)
In-Reply-To: <2ea1731b0906212333r20deb71q2f021fc79bcc8a8e@mail.gmail.com>

> > How do you handle hard-links, then?
> 
> Indeed hard-links are not supported :) Due to the design of this fs
> there are some limitations explained in the documentation as not
> hard-link, only private memory mapping and so on. However this
> limitations don't limit the fs itself because you must consider the
> special goal of this fs.

I did not see that in the changelog. If it is not general purpose
filesystem, it is lot less interesting.

> >> >From performance point of view:
> >>
> >> Sometimes ago I uploaded here (http://elinux.org/Pram_Fs) some benchmark
> >> results to compare the performance with and without XIP in a real
> >> embedded environment with bonnie++. You could use it as reference point.
> >
> > Well, so XIP helps. ext2 can do XIP too, IIRC. Is your performance
> > better than ext2?
> >
> > Wait... those numbers you pointed me... claim to be as slow as
> > 13MB/sec. That's very very bad. My harddrive is faster than that.
> 
> As I said I did the test in a real embedded environment so to have
> comparable result you should use the same environmente with the same
> tools, with the same workload and so on.

Even on real embedded hardware you should get better than 13MB/sec
writing to _RAM_. I guess something is seriously wrong with pramfs.

								Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

  reply	other threads:[~2009-06-22 17:20 UTC|newest]

Thread overview: 53+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-06-13 13:20 [PATCH 00/14] Pramfs: Persistent and protected ram filesystem Marco
2009-06-13 13:41 ` Daniel Walker
2009-06-13 15:59 ` Jamie Lokier
2009-06-14  7:15   ` Marco
2009-06-14 11:08     ` Artem Bityutskiy
2009-06-15 15:51       ` Bryan Henderson
2009-06-15 17:42         ` Marco
2009-06-14 11:46     ` Jamie Lokier
2009-06-14 16:04       ` Marco
2009-06-16 15:07         ` Jamie Lokier
2009-06-16 19:15           ` Marco
2009-06-24 17:41             ` Jamie Lokier
2009-06-25  6:44               ` Marco Stornelli
2009-06-26 11:30                 ` Jamie Lokier
2009-06-26 16:56                   ` Marco
2009-06-24 14:21                     ` Pavel Machek
2009-06-21  6:40     ` Pavel Machek
2009-06-21 17:34       ` Marco
2009-06-21 20:52         ` Pavel Machek
2009-06-22  6:33           ` Marco Stornelli
2009-06-22 17:20             ` Pavel Machek [this message]
2009-06-22 17:31               ` Tim Bird
2009-06-22 17:37                 ` Pavel Machek
2009-06-22 18:07                   ` Marco
2009-06-22 20:40                     ` Henrique de Moraes Holschuh
2009-06-22 20:40                     ` Pavel Machek
2009-06-22 21:50                       ` Tim Bird
2009-06-22 21:57                         ` Pavel Machek
2009-06-22 22:38                           ` Pavel Machek
2009-06-22 23:26                             ` Chris Friesen
2009-06-23  1:42                               ` David VomLehn
2009-06-23 18:07                           ` Marco
2009-06-23 18:29                             ` Pavel Machek
2009-06-24 17:47                               ` Jamie Lokier
2009-06-25  6:32                                 ` Marco Stornelli
2009-06-22 18:55                   ` Tim Bird
2009-06-22 21:02                     ` Pavel Machek
2009-06-22 22:02                       ` Tim Bird
2009-06-22 18:08                 ` Marco
2009-06-15 17:15 ` Tim Bird
2009-06-15 17:44   ` Marco
2009-06-15 17:58     ` Tim Bird
2009-06-17 18:32 ` Chris Friesen
2009-06-18  6:35   ` Marco Stornelli
     [not found] <4a4254e2.09c5660a.109d.46f8@mx.google.com>
2009-06-24 16:49 ` Marco
2009-06-24 17:38   ` Marco
2009-06-24 17:59     ` Pavel Machek
2009-06-25  6:30       ` Marco Stornelli
2009-06-28  8:59         ` Pavel Machek
2009-06-28 16:44           ` Marco Stornelli
2009-06-28 17:33           ` Marco Stornelli
2009-07-09 23:42             ` Pavel Machek
2009-06-24 17:46   ` Pavel Machek

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