On 08/18/16 21:15, Warner Losh wrote:
On Thu, Aug 18, 2016 at 6:56 AM, Allan Jude <allanj...@freebsd.org> wrote:
On 08/18/16 05:50 AM, Dag-Erling Smørgrav wrote:
Nathan Whitehorn <nwhiteh...@freebsd.org> writes:
OK. In which configurations? My Dell servers, for instance, don't do
this. How are they set up? What drivers are being used? Is this
something that affects passthrough disks, RAIDs, disk images?
Most LSI MegaRAID controllers don't have real passthrough, only JBOD.
You can query the drive with "camcontrol identify passX", but the
controller does not report a stripe size for the volume (mfidY).
The point is that *if the reported stripe size is wrong*, more things
than partition alignment in the installer will suffer for it.
It's not wrong, it's non-existent, and I'm getting really tired of
repeating myself.
Fixing the installer with a bandaid in the run-up to a release is
fine, but *we need to fix the underlying problem*.
We can't, because hardware sucks, and I'm getting really tired of
repeating myself.
DES
Which makes more sense:
A) If stripesize == 0, use some sane value like 4096
I don't like this.
B) Some other combination that uses the reported stripe size, unless it
is 0, in which case it uses 4096 (or some other value controlled by a
different new sysctl)
Don't like this so much.
C) create kern.geom.min_stripe_size with a default of 512, but users can
set 4096 if they use only 4k devices. (doesn't really solve the problem
for the installer)
Default it to 4k, and allow users to set it to 512. If the drive
reports < this value
report this value instead. You'll need to make this a tunable. Then the upper
layers wouldn't care. There's a small chance that some SD cards might be
reporting values that are too large. But I think it is confined to SD cards and
if I see too many more I'll do something specific in the SD driver.
Warner
That sounds good to me and I think can clean up a lot of code and
potential foot-shooting. Who is planning to make the patch? I'm happy to
do anything that would be helpful.
-Nathan
_______________________________________________
svn-src-head@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/svn-src-head
To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
