[EMAIL PROTECTED] (Jeff Davis) writes: > On Wed, 2006-09-06 at 22:12 -0400, Christopher Browne wrote: > >> > Can you elaborate a little? Which filesystems have been problematic? >> > Which filesystems are you more confident in? >> >> Well, more or less *all* of them, on AMD-64/Linux. >> >> The "pulling the fibrechannel cable" test blew them all. XFS, ext3, >> JFS. ReiserFS was, if I recall correctly, marginally better, but only >> marginally. >> >> On AIX, we have seen JFS2 falling over when there were enough levels >> of buffering in the way on disk arrays. > > Well, that's interesting. I suppose I can't count on the filesystem > as much as I thought. Are you implying that the filesystems aren't > ready on 64-bit?
I don't think this necessarily is a 64 bit issue; it's more that with the more esoteric, expensive disk array hardware, there are fewer with the ability to test it, because you need $200K worth of hardware around to do the testing. > Is it more of a hardware issue (a controller lying about the > security of the write)? Any comments on FreeBSD/UFS+SU? I would > expect UFS+SU to have similar issues, since it depends on write > ordering also. > > What do you do for better data security (aside from the obvious > "don't pull cables")? The last time we looked, FreeBSD wasn't an option at all, because there wasn't any suitable FibreChannel support. That may have changed; haven't researched lately. The trouble that the NILFS people pointed out seems a troublesome one, namely that the more levels of cacheing (even if battery-backed), the less certain you can be that the hardware isn't lying about write ordering. I haven't got an answer... -- let name="cbbrowne" and tld="cbbrowne.com" in String.concat "@" [name;tld];; http://linuxdatabases.info/info/multiplexor.html Jury -- Twelve people who determine which client has the better lawyer. ---------------------------(end of broadcast)--------------------------- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly
