I'm about to upgrade to more disk space and I'm tempted use this as an opportunity to get two disks and implement gmirror. Before I go ahead there's a few aspects of mirroring I'm not sure about and would appreciate some advice.
I'm using grub for multi booting. Does this introduce any problems if I want to boot into Windows or Linux on one of the other partitions? The gmirror manpage describes the procedure for handling kernel dumps using the prefer balance algorithm in the early stages of booting and then switching to round-robin in the /etc/rc.local script. It then goes on to say that "If on the next boot a component with a higher priority will be available, the prefer algorithm will choose to read from it and savecore(8) will find nothing". Does this only arise if I've made some change to the configuration of the mirror between the dump and the reboot or is there some instances when the priority automatically changes? Some of the articles I've read about gmirror suggest setting the balance to round-robin while others just leave this at the default setting of split. Am I right in assuming that round-robin would give better performance, and does it make much noticeable difference in real terms. In particular am I likely to see a reduction in performance using gmirror compared with what I would get with just a normal single disk. Finally, recent articles say to set kern.geom.debugflags to 17 when creating a mirror on a mounted drive while older articles say to set it to 16. Although I'll probably be creating the mirror on my disks before copying my system onto them so I don't really need to worry about setting this flag but I'm curious to know the difference between using the two values. -- Mike Clarke _______________________________________________ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
