On Wed, Aug 18, 2010 at 07:07:34PM -0700, Darrick J. Wong wrote: > Oddly, I ran the entire suite of tests against a larger set of machines, and > with Tejun's RFC patchset I didn't see nearly as much of an improvement. I > have been trying to put together a new tree based on "replace barrier with > sequenced flush" and Christoph's "explicitly flush/FUA" patch sets, though I've > gotten lost in the weeds. :( Tejun's patches don't allow concurrent cache flushes to happen, while my patch did. Tejun said there are drivers that can't handly empty flushes with a bio attached, making this nessecary. Tejun, any idea what drivers that would be? > I also experienced some sort of crash with Tejun's relaxed barrier patch on one > of my systems. I was hitting the BUG_ON in drivers/scsi/scsi_lib.c, line 1115. My kernel source doesn't have a BUG_ON line there, but only one two lines above. A req->nr_phys_segments that's zero sounds a bit like empty flush requests, I'll need to look into it again. -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
