On Thu, Nov 01, 2012 at 11:56:18AM +0100, Sander wrote:

quoted

For now, I'll stick with 3.5.3 for a while to make sure my drive is actually
ok (it seems to be afterall), and once I'm happy that it's the case, I'll go
back to 3.6.3 with serial console remote logging and try to capture the full
sata failure I got with 3.6.3.

Thanks for the info. You could put some load on the ssd to see if you
can trigger an issue under 3.6.3(+) with btrfs filesystem scrub or
badblocks (in the default non-destructive mode).

I'll try this in a few days when I've first comfirmed that my SSD is still
100% stable under 3.5.3 (so far it is).
After that, I'll go back to 3.6.3 and see what it takes to crash it.
But as per my original report and
http://marc.merlins.org/tmp/crash.jpg
this does look like a sata layer problem, which btrfs isn't responsible for.

Also there is still that unaddressed bug that when it does happen, btrfs
then can end up in a state where the filesystem is unmountable without
manually fixing it.
 

Can you collect SMART data (with smartctl) from the ssd?

I did actually have a look, but to be honest, SSDs have pretty useless smart
data overall. Mine's likely a bit worse than the average even.

gandalfthegreat:~# smartctl -a /dev/sda
smartctl 5.41 2011-06-09 r3365 [x86_64-linux-3.5.3-amd64-preempt-noide-20120903] (local build)
Copyright (C) 2002-11 by Bruce Allen, http://smartmontools.sourceforge.net

=== START OF INFORMATION SECTION ===
Device Model:     OCZ-VERTEX4
Serial Number:    OCZ-26W4VJ3SP32E1WC2
LU WWN Device Id: 5 e83a97 59be3b57e
Firmware Version: 1.5
User Capacity:    512,110,190,592 bytes [512 GB]
Sector Size:      512 bytes logical/physical
Device is:        Not in smartctl database [for details use: -P showall]
ATA Version is:   9
ATA Standard is:  Exact ATA specification draft version not indicated
Local Time is:    Thu Nov  1 09:14:43 2012 PDT
SMART support is: Available - device has SMART capability.
SMART support is: Enabled

=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED

General SMART Values:
Offline data collection status:  (0x00)	Offline data collection activity
					was never started.
					Auto Offline Data Collection: Disabled.
Self-test execution status:      ( 249)	Self-test routine in progress...
					90% of test remaining.
Total time to complete Offline 
data collection: 		(    0) seconds.
Offline data collection
capabilities: 			 (0x1d) SMART execute Offline immediate.
					No Auto Offline data collection support.
					Abort Offline collection upon new
					command.
					Offline surface scan supported.
					Self-test supported.
					No Conveyance Self-test supported.
					No Selective Self-test supported.
SMART capabilities:            (0x0003)	Saves SMART data before entering
					power-saving mode.
					Supports SMART auto save timer.
Error logging capability:        (0x00)	Error logging NOT supported.
					General Purpose Logging supported.
Short self-test routine 
recommended polling time: 	 (   0) minutes.
Extended self-test routine
recommended polling time: 	 (   0) minutes.

SMART Attributes Data Structure revision number: 18
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE
  1 Raw_Read_Error_Rate     0x0000   006   000   000    Old_age   Offline      -       6
  3 Spin_Up_Time            0x0000   100   100   000    Old_age   Offline      -       0
  4 Start_Stop_Count        0x0000   100   100   000    Old_age   Offline      -       0
  5 Reallocated_Sector_Ct   0x0000   100   100   000    Old_age   Offline      -       8
  9 Power_On_Hours          0x0000   100   100   000    Old_age   Offline      -       1210
 12 Power_Cycle_Count       0x0000   100   100   000    Old_age   Offline      -       240
232 Available_Reservd_Space 0x0000   100   100   000    Old_age   Offline      -       8019542246
233 Media_Wearout_Indicator 0x0000   099   000   000    Old_age   Offline      -       99

SMART Error Log not supported
Warning! SMART Self-Test Log Structure error: invalid SMART checksum.
SMART Self-test log structure revision number 1
No self-tests have been logged.  [To run self-tests, use: smartctl -t]


Device does not support Selective Self Tests/Logging

Marc
-- 
"A mouse is a device used to point at the xterm you want to type in" - A.S.R.
Microsoft is to operating systems ....
                                      .... what McDonalds is to gourmet cooking
Home page: http://marc.merlins.org/