On Thu, Jun 12, 2008, Erik de Castro Lopo wrote: > In the above situation we are seeing machines have difficulty > when coming up after a powerloss. I suspect that we end up with > problems that even Ext3's journalling isn't enough to cope with > and I suspect that its actually the loss of disk metadata which > is causing the problems.
[snip] > Does anyone have anything else to suggest? Invest in small UPSes and cleanly shut the server down on shutdown? Can you enable entire journalling, rather than just metadata journalling? Can you disable write-caching on the disks, so the disks aren't lying when they say they've committed some stuff to disk? I seem to recall there are brands of disks which will go to great lengths to lie to you that the data is on the disk when its still in cache, all in the name of (windows) performance. Its funny, as the whole argument with the ext3 journalling block device versus the XFS journalling was to work better on PC-class hardware. (Ie, when you don't have enormous PSU Capacitors and an NMI which get triggered on power-loss, giving you just enough juice to tell the disk controllers to -STOP- and not scribble random crap over important metadata sections. God, where'd that email get to?) Adrian (Anyone remember why Linux ext2's defaults versus BSD FFS's defaults were so bad?) -- - Xenion - http://www.xenion.com.au/ - VPS Hosting - Commercial Squid Support - - $25/pm entry-level VPSes w/ capped bandwidth charges available in WA - -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
