On Fri, 4 Jan 2002, Michael Glickman wrote:

> Using storage memory is less efficient than using dynamic heap for write
> access, because data storage area is write protected, so that you need
> DmWrite or something equivalent (istead of just placing the data, as in
> case of dynamic storage), which involves a trap to overcome write
> protection.  However for reading you souldn't have this problem.

Yeah, I realize it's less efficient in that respect.  What I'm trying to
find out is how much less.  If it's enough for a noticeable slow-down then
I'll figure out something else.  At most I'll be doing one write per
display line (with possible scrolling of the buffer once I reach the end
of the fixed space), and I could easily optimize that for one DmWrite call
per call to the output function (since one call could produce a few lines
of word-wrapped output).

> That might be the way to go. Assuming you keep your documents in the
> data base, you can probably read straight from the data storage (with no
> need to copy them to dynamic heap); I assume you lock only handles for
> the records which are currently displayed, otherwise that could get
> PalmOS terribly engaged. 

I'd only be locking them as they were used, when writing output to a
window (hidden or visible) and when reading for a redraw.  The latter
could be a lot of unlocking and locking when using the scrollbar, but I'm
not sure what the overhead is there.  I do intend to read straight from
the database in the display code.

-----------------------------------------------------------------------
Brian Smith // avalon73 at arthurian dot nu // http://www.arthurian.nu/
Software Developer  //  Gamer  //   Webmaster  //  System Administrator
"Buckle your seatbelt, Dorothy, 'cause Kansas is going bye-bye." -Cypher


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