Although I know there are opinions all over the map, there has never been a concrete, universal reason not to use extremely small records in PDBs until now.
Taken literally, I'd agree that small records was not so much the problem as
"large" record counts. IMHO, the definition of "large" in this context is
around 8-10K records.
I think you're right that if there was a historical problem, it was with large record counts, but even now, that problem hasn't changed. If you have a billion records, you incur storage overhead, and your HotSyncs take forever. That's always been the case, and we're well aware of it. But I think we agree that this whole small-records-are-no-longer-allowed-to-be-small thing is new, weird, and at least in this case, undesirable.
It is also obvious that it is different by looking at the ratio of total size to
data size on other devices beside the T5. On all the devices I've tried from OS
3.5 to OS5.x, the difference is 84 bytes base overhead, plus *20* bytes per
record (not 8 as in the desktop format), plus appinfo or sortinfo blocks.
But that 20 byte figure is subject to change, and I understand it has not always
been the same size. At 30K records, that means you have about 600K of record
header overhead which you could mostly eliminate, even on other devices.
Again, we really don't care about the header overhead, but I do think you're right, the mere fact that the devices have no rules about the in-memory PDB format does make it a slippery slope. The ideal solution to this is akin to what Ben described initially; we need a way to specify to NVFS that a database doesn't need padding. Even flipping the read-only bit should be enough, for God's sake. Let PalmOne release a ROM upgrade to make that possible, and we'll totally shut up.
But at this point, I think we've had our few days to whine about it. We're more or less where we were when we started, intellectually (I don't think there's any substantive reason why our database should have been architected differently), but reality calls. I appreciate everybody's suggestions, I'm sure we'll figure something out...
-d
-- For information on using the Palm Developer Forums, or to unsubscribe, please see http://www.palmos.com/dev/support/forums/
