Questions around XML and file size

[Shane]

Hello -

One of our projects is developing a tool for contractor time entry that
involves inputing time via XML.

They have noticed that after saving the project plan as XML the plan size is
significantly bigger (ok this is expected) but when they save the plan back
as mpp the plan size has doubled from its original size.

While investigating this I notiiced the same behaviour without making any
changes to the plan at any time some I'm wondering what is happening within
the plan that causes this.

Is there anything that we should look out for that is causing this?

Any help is appreciated.

Regards,
Shane

 

[Gary Chefetz]

Shane:

What version are you using? This sounds like 2003. I would suggest moving to
2007 if you're going to use XML conversions regularly

 

[Shane]

Hi Gary -

We brought this to Microsoft (to get peace of mind if nothing else). Here is
what they said:

The size increase is because of the baseline data. Like any timescale data
in Project, timephased baseline data is stored in relation to a calendar.
What this ultimately means is that storing baseline data can be very
expensive depending on how the baseline data is entered and depending on the
calendars surrounding it. In this particular case, Baseline 0 and 1 are both
set. Now, in the MPP file, the data has been stored in a more compact way,
but when the XML file is read in, Project isn’t able to recreate the same
compact baseline segments in order to keep the file size down. Thus, even
though you have the same baseline data, it’s now stored in a less compact way
just because of the way it was reconstructed when read back from the XML
format. If you look at the way the XML format is by default, everything is in
little chunks and so Project can’t recreate everything back to larger more
compact chunks of data.

PS - It was 2007

Regards,
Shane

 

[Gary Chefetz]

Good answer. Spinning out multiple layers of time-phased data certainly
creates a lot of XML.