Re: Reiser4. BEST FILESYSTEM EVER - Christer Weinigel

["David H. Lynch Jr" <dhlii@comcast.net>]

Christer Weinigel wrote:
>
> To misquote Scott Adams: I'm not anti-Reiser4, I'm anti-idiot.  
>
>   /Christer
>   
    So can we ignore the benchmarks issue entirely and deal with the
issue of what might it actually take now that Hans is not pissing all
over everyone to get Reiser4 submitted with some hope of being accepted ?

    Your analysis was excellent. It make the case that just is there
will be a few cases where Reiser4 is absolutely compelling and a few
cases where it makes no sense at all that there are alot of cases in the
middle.

    I can keep coming up with examples where the attributes unique to
Reiser4 are an excellent idea, and you can just as easily come up with
cases where it is a bad idea.
   
    If the standard is that it must be all things to all people, then we
need to quit letting any filesystems in.
   
    Let's say John takes your advice and tweaks bonnie or builds
whatever benchmark test bed you want, and proves Reiser4 outperforms
everything in all cases (highly unlikely)
    does that mean it should get it ?
    What about if it is 10% slower in most normal cases ? Is that a good
enough reason for excluding it ?
    Is anyone ready to claim that there are no cases (beyond the
extremely rare case of compressing zero's) where Reiser4 may prove to be
the best choice ?
   
    Compression itself is almost a religious war subject. for some
people it is ALWAYS a bad idea, to others it is ALWAYS a good idea.
    In the real world it varies. Application level compression is
generally superior to filesystem compression - there is more knowledge
about the data leading to better choice of compression algorithms.
    and fortunately Linux provides one of the best environments for
incorporating application level compression.
    But generally is not the same as ALWAYS.
    While I raised a specific case I was aware of where my understanding
was compressed data could result in a net overall gain in performance -
network servers where compression decompression were handled at the
client, several other instances have been raised.
    Depending on the speed of the CPU, size of memory, size and speed of
cache, speed of disk, type of data, ....
    sometimes compressed data will not only save space but improve
performance - and sometimes it will be costly to performance.
    That does not make it a bad idea. We have several scheduling
algorithms, because one size does not fit all.

    Besides I doubt given the complexity of the issue that John or
anyone else can put together a benchmark that I can't poke holes in.
    There are so many cases that there is no such thing as the general
case. Even performance compressing zeros starts to almost look like a
rational measure when you start to calculate all the
    permutations in the data compression matrix.
   
   



-- 
Dave Lynch 					  	    DLA Systems
Software Development:  				         Embedded Linux
717.627.3770 	       dhlii@dlasys.net 	  http://www.dlasys.net
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Over 25 years' experience in platforms, languages, and technologies too numerous to list.

"Any intelligent fool can make things bigger and more complex... It takes a touch of genius - and a lot of courage to move in the opposite direction."
Albert Einstein