[fitsbits] Bintable proposals

[Thierry Forveille]

Mark Calabretta writes:
 > Preallocating disk space is irrelevant if you're writing to tape!  Anyway,
 > is it really necessary these days? 
Actually, I would say that tapes, not disks, are on their way to irrelevance
for really massive datasets. The fact is that the characteristic time scale
in Moore's law has recently been twice longer for tapes (36 months, on both
speed and capacity) than disks (18 months, again on speed and capacity). Disks
are currently about 10 times faster than tapes (setting VLBI tapes aside),
so the overhead of a disk buffer (not to speak of RAM) is close to negligible.
Tape writing on the other hand represents a true bottleneck. For our 
forthcoming CCD survey (with an 18k x 18k mosaic, with 30s readout time)
we are very seriously considering the option of shipping hard-drives
instead of ever writing a tape...

Thierry Forveille
CFHT