extremely slow boot of RELENG_10

[mike tancsa]

On 7/31/2019 11:59 AM, Eugene Grosbein wrote:
> 31.07.2019 22:30, mike tancsa wrote:
>
>> While moving a pair of ZFS disks from an *very* old motherboard to a new
>> one, I ran into an odd problem I had not seen before.  The box was
>> running just fine RELENG_10 from FreeBSD 10.1-STABLE #18 r279918 on 10yr
>> old MB. Boots normally and expected speeds for old hardware/CPU.  But on
>> the new one, as soon as the |\-/|\ starts spinning, it looks like its
>> 1/100th of the speed it should be.  Unfortunately, we didnt have the
>> luxury to wait for it to boot up all the way.  We put the disks back in
>> the old motherboard, did the RELENG_11 upgrade which included putting in
>> the new boot blocks after zpool upgrade and then the disks booted just
>> fine in the new box.  We at first thought it was a hardware issue, but
>> same behaviour on another new MB, new SATA cables etc etc.
>>
>> Any idea what was going on behind the scenes that might have caused it
>> ?  Is there something about the way the old boot blocks would interact
>> poorly with new motherboards (in this case, a SuperMicro X11SSH-F) ?
> Maybe it attempted dual-console boot involving output to serial port...
>
As upgrading to RELENG_11 and upgrading the boot blocks fixed the issue
for this particular instance, I dont have the image anymore to boot /
test from. However, it was just as slow on serial console as it was on
the regular console.  I do have the files on an old snapshot

#cd /.zfs/snapshot/7/boot

# ls -l | egrep "pmb|boot"
-r--r--r--   1 root  wheel  uarch   8192 Mar 12  2015 boot
-r--r--r--   1 root  wheel  uarch    512 Mar 12  2015 boot0
-r--r--r--   1 root  wheel  uarch    512 Mar 12  2015 boot0sio
-r--r--r--   1 root  wheel  uarch    512 Mar 12  2015 boot1
-r-xr-xr-x   1 root  wheel  uarch  33811 Mar 12  2015 boot1.efi
-r--r--r--   1 root  wheel  uarch 819200 Mar 12  2015 boot1.efifat
-r--r--r--   1 root  wheel  uarch   7680 Mar 12  2015 boot2
-r--r--r--   1 root  wheel  uarch   1185 Mar 12  2015 cdboot
-r--r--r--   1 root  wheel  uarch  16016 Mar 12  2015 gptboot
-r--r--r--   1 root  wheel  uarch  42128 Mar 12  2015 gptzfsboot
-r--r--r--   1 root  wheel  uarch    512 Mar 12  2015 pmbr
-r--r--r--   1 root  wheel  uarch 264192 Mar 12  2015 pxeboot
-r--r--r--   1 root  wheel  uarch 300290 Mar 12  2015 userboot.so
-r--r--r--   1 root  wheel  uarch  66048 Mar 12  2015 zfsboot

I am more just trying to understand what might have been going on. I
have a couple of other old RELENG_10 boxes in production still. If I had
to swap out hardware without being able to do an OS upgrade, I want to
understand how best to work around this issue (whatever it is) if possible

    ---Mike