[Info-vax] Anyone interested in another public access system

[FredK]

"Richard B. Gilbert" <rgilbert88 at comcast.net> wrote in message 
news:8_SdnVfP4607PX7UnZ2dnUVZ_iydnZ2d at giganews.com...
> FredK wrote:
>> "Richard B. Gilbert" <rgilbert88 at comcast.net> wrote in message 
>> news:BtydneYdGuPi-37UnZ2dnUVZ_oydnZ2d at giganews.com...
>>
>>> Isn't there an ODS-5 now?  ISTR reading about the new file system that 
>>> allows all kinds of special characters in filenames.
>>>
>>> I've been using ODS-2 for a bit more than 23 years now.  It does just 
>>> about everything I need in a file system.  Needless to say, I do NOT 
>>> need files named #@!$$xqb.|\23^@# or any other such frippery!
>>>
>>> I know, I know, I'm hopelessly old fashioned.
>>
>> ODS-5 is ODS-2 with extended name support.  Recently we've even tacked on 
>> UNIX hard and soft links.
>>
>> But the basic problem is that the file system is a living antique of 
>> design and is very slow compared to a modern file system.
>>
>
> I never noticed this slowness.  Perhaps I just wasn't paying attention.
>
> What would you cite as an example of a "modern" file system?  Most Unix 
> systems won't even commit your file to disk until they get around to it. 
> One of the nice things about VMS is that what you write to disk is 
> actually committed to disk within a few seconds.  A power failure does not 
> always require repairs to a VMS file system; something that can't be said 
> for Unix.  Unix provides no means to create a contiguous file; just 
> splatter it all over the disk!.  Even <obligatory retching noises> Windows 
> has a utility to make your files and free space contiguous. Unix just 
> doesn't care.
>
> Except for Sun's ZFS, I think most Unix file systems have changed very 
> little in the last ten or twenty years.
>

Except for some extensions, ODS hasn't changed much since the PDP11 and 
RSX11M.  ODS suffers in terms of very large files, and very large numbers of 
files.  Take a look at a file system like XFS (SGI circa mid-to-late 
1990's).

As to the pro's and con's of file system caching, would it not be better if 
the user (or programmer) could determine how critical the data is?  On a 
UNIX system, a temporary file might be created and deleted without any of 
the bits ever hitting a physical disk.  If that file was transient data - 
why would you care that it was cached?  Or if the file structure was ever 
updated?

http://www.oss.sgi.com/projects/xfs/papers/xfs_usenix/index.html