Even with current stable kernel 3.6.2 I sometimes get those syslog messages :


2012-10-15T19:37:58.401+02:00 n22 kernel: EXT4-fs error (device sdb3): ext4_mb_generate_buddy:741: group 436, 22902 clusters in bitmap, 22901 in gd
2012-10-15T19:37:58.417+02:00 n22 kernel: JBD2: Spotted dirty metadata buffer (dev = sdb3, blocknr = 0). There's a risk of filesystem corruption in case of system crash.
2012-10-15T19:38:03.335+02:00 n22 kernel: EXT4-fs error (device sdb3): mb_free_blocks:1300: group 436, block 14294559:freeing already freed block (bit 7711)

when I run an almost stable Gentoo booted from an external USB disk.
I didn't configured too much exotic things, just this is worth to mention :

$> cat /proc/sys/vm/dirty_writeback_centisecs
1000


-- 
MfG/Sincerely
Toralf Förster
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