Messages in this thread |  | | Date | Sat, 6 Oct 2001 00:05:27 +0200 | From | Pavel Machek <> | Subject | Re: [POT] Which journalised filesystem ? |
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Hi!
> > > > We (as in Linux) should make sure that we explicitly tell the disk when > > > > we need it to flush its disk buffers. We don't do that right, and > > > > because of _our_ problems some people claim that writeback caching is > > > > evil and bad. > > > > > > Does this even work right for IDE ? > > > > Current IDE drives it may be a NOP. Worse than that it would totally ruin > > high end raid performance. We need to pass write barriers. A good i2o card > > might have 256Mb of writeback cache that we want to avoid flushing - because > > it is battery backed and can be ordered. > > If the cache is small and is primarily a track cache (IDE) one trick that > we can do is to flood the cache with data so everything is forced out. > > We can do this at mkfs time, (so even destructive tests are allowed) > and we can probe how to make this work for a particular drive. And > then the kernel can just use the results of that probe.
How do you probe this without actually powering system down? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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