I am setting up an Oracle server for a new manufacturing/POS application in
my department. Although haven't had much experience with the new package
that will sit on top of Oracle, I suspect our database will be small-to-tiny
by Oracle standards; certainly less than 1GB, relatively low volume, etc
(indeed, most of the functionalilty was being met by Rbase in Netware
environment not that long ago). So likely a moot point for our size, but
would like to have some idea about placement of files.
- How is Oracle when putting datafiles, etc on souped up UFS, journaled
file systems, etc (in particular AdvFS for Digital Unix)? Any problems or
disadvantages to doing such?
- A number of references suggest mirroring the online redo log files. How
necessary is this? If I am not mirroring the redo log files, and they get
damaged, how catastrophic is it? Presumably I only lose everything that was
in the damaged redo logs and later (and presumably later should not be a very
long time as database should be crashing.) And I would hope that it would
crash shortly after the damage, so that if my redo logs are filling up every
four hours or so, worst case is I lose the last 4hrs of data entry. Or will
it wait until the damaged redo log becomes active again, which with 3-4 redo
logs would lose about 2 workdays, which is becoming unnacceptable.
- Is mirroring of on line redo logs and archived redo logs independent of
each other? Ie, can I mirror one and not the other. It would seem silly
to mirror online redo logs but not archived logs, or am I missing something.
- Several refeneces suggest that redo logs and archived redo logs not be
put on the same disk to avoid disk contention. I suspect that won;t be a
major issue for me (realtively small, low volume database), but was curious.
Since archive redo logs are just copies of online redo logs after they're
full, shouldn't it just be a matter of of ORacle logwriter(? forget name)
process just renaming the the full online redo log to the archive log name
and opening a new redo log (ie no need to actually copy file, just adjust some
directory entries), or does it actully copy the individual data blocks.
Just seems a pain, since online redo logs are likely to be rather small
(compared to data files, etc) but also relatively high activity --- seems to
me they would go nicely on the same phsyical disk (unlike everything else in
oracle which seems to like a physical disk for each file).
Thanks in advance for all your feedback. I have tried to read up but
experience is not readily replaced by books.
Tom Payerle
Dept of Physics payerle_at_physics.umd.edu
University of Maryland (301) 405-6973
College Park, MD 20742-4111 Fax: (301) 314-9525
--
Tom Payerle
Dept of Physics payerle_at_physics.umd.edu
University of Maryland (301) 405-6973
College Park, MD 20742-4111 Fax: (301) 314-9525
Received on Thu May 27 1999 - 20:42:31 CDT
