Re: [PATCH 00/14] Pramfs: Persistent and protected ram filesystem

Pavel Machek
2009-06-22T17:20:24Z

> > 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
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