[rrd-developers] implementing portable format

[Tobias Oetiker]

Hi Hamish,

Yesterday Hamish Marson wrote:

> Quoting kevin brintnall <kbrint at rufus.net>:
>
> > I have some more ideas on the implementation...  I tried to list the
> > categories in increasing order of difficulty.  I'm sure I'm missing a few
> > gotchas, but these strike me as the major categories that need work.
> >
> > Looking for feedback on these...  Let me know if I'm off-base.
> >
> > -----------------------------------------------------------------
> >
> > CHOICE OF ON-DISK ENCODING:
> >
> > * estimate user base, choose most common architecture for native format
> >      - probably i386?
> >
> > * choose a specific byte-string for RRD portable NAN, INF.  Conversion
> >   routines will have to test specifically for this and convert between
> >   "RRD NAN" and "native NAN".
> >
> > -----------------------------------------------------------------
> >
>
> [deleted]
>
> As long as it's noted in the header, what sort of format various
> numbers are encoded as, what about making the reading of any type
> possible, but only write in the native format... Thus if an RRD is
> opened in read-write mode, have rrdtool able to convert an RRD from
> the encoded format into native format... (Either using something like
> 'rrdtool convert' or with a flag to 'rrdtool update' to doit
> automatically - which would only happen once of course).

> This would let things like rdrdgraph able to operate still without
> conversion, but make it possible to move files across easily from one
> architecture to another... I can't see anyone would ever want to write
> to the same RRD from multiple architectures simultaneously...

This sounds like quite a bit of added complexity. It would
require us to be able to convert from all platforms to all other
platforms ... I have the feeling that adding one new format with
the ability to read the old one already puts quite something on our
plate.

cheers
tobi



-- 
Tobi Oetiker, OETIKER+PARTNER AG, Aarweg 15 CH-4600 Olten, Switzerland
http://it.oetiker.ch tobi at oetiker.ch ++41 62 775 9902 / sb: -9900