[Info-vax] improve performance of /EXCLUDE

[mcleanjoh at gmail.com]

On Tuesday, January 27, 2015 at 10:24:18 PM UTC+11, Stephen Hoffman wrote:
> On 2015-01-27 04:56:53 +0000, David Froble said:
> 
> > Stephen Hoffman wrote:
> >> On 2015-01-26 23:27:51 +0000, David Froble said:
> >> 
> >>> I'm thinking that the usage of a feature might have some bearing on 
> >>> additional work on that feature.
> >>> 
> >>> How many times in a second do you perform such operations?
> >>> ...
> >>> For a one time interactive operation, maybe not so much ....
> >> 
> >> Incorporate a modern search engine into VMS.   That would be beneficial 
> >> to more folks, more often.
> > 
> > The discussion is not about something missing, it's about an existing 
> > capability that might not be as efficient as possible.
> 
> You seem to think I wasn't commenting about the /EXCLUDE.   With a 
> faster integrated search, there wouldn't be this discussion, or there'd 
> be a discussion of the search grammar necessary for a custom search -- 
> this assuming that /EXCLUDE didn't go directly to the fast search 
> itself.
> 
> > Are you enjoying your "Christmas catalog" ?
> > 
> > :-)
> 
> Um, I'm more interested in seeing VMS not continue to implode.  Fast 
> searches are now expected.  Well, expected for those folks that've 
> experienced them.
> 
> 
> -- 
> Pure Personal Opinion | HoffmanLabs LLC


Isn't this mainly a factor of the respective file systems?  Linux/Unix is just a stream of bytes on disk whereas RMS is designed to provide a variety of commercial useful file structures (e.g. Indexed).

It's expecting a lot to believe that searching compressed data in an indexed file will be as fast as a simple pattern match in a stream of bytes.  Also a Linux/Unix search would have fewer overheads when determining the start and end of the record than VMS which has to use the specific record type and formatting information to try to figure out where the record starts and ends.

All that said, the /EXCLUDE=(filespec[,filespec ...]) shouldn't be reading the "excluded" files and suppressing the output.  This makes no sense when it should be easy to identify and ignore those files.