> > Other db's have commands for:
> > start/end external backup
I see that the analogy to external backup was not good, since you are correct
that dba's would expect that to stop all writes, so they can safely split
their mirror or some such. Usually the expected time from start
until end external backup is expected to be only seconds. I actually think we
do not need this functionality, since in pg you can safely split the mirror any
time you like.
My comment was meant to give dba's a familiar tool. The effect of it
would only have been to create a separate backup of pg_control.
Might as well tell people to always backup pg_control first.
I originally thought you would require restore to specify an xlog id
from which recovery will start. You would search this log for the first
checkpoint record, create an appropriate pg_control, and start rollforward.
I still think this would be a nice feature, since then all that would be required
for restore is a system backup (that includes pg data files) and the xlogs.
Andreas