panic : free : freeing free frag

[Tom Gorodecki]

We have here a Sun 4/280 which is a disk server to few Sun WS.  At least
ones a day i got the following panic:

/ud2: file system full
/ud2: file system full
/ud2: file system full
itrunc: /ud2/80491 new size = 0, blocks = -48
itrunc: /ud2/135867 new size = 0, blocks = -16
dev = 0x308, block = 6245, fs = /ud2
panic: free: freeing free frag
syncing file systems... [8] [7] [4] [1] [1] [1] [1] [1] [1] [1] [1] [1] [1] [1] [1] [1] [1] [1] [1] [1] done

dumping to vp ff005f88, offset 69182
SunOS Release 4.0_Export (TASU20) #2: Wed Aug 10 15:58:05 GMT+0200 1988
Copyright (c) 1988 by Sun Microsystems, Inc.
mem = 32768K (0x2000000)
avail mem = 32325632
Ethernet address = 8:0:20:0:d0:f6
xyc0 at vme16d16 0xee40 vec 0x48 
xy0 at xyc0 slave 0
xy0: <Hitachi DK815-10 cyl 1735 alt 2 hd 15 sec 67>
xy1 at xyc0 slave 1
xy1: <Hitachi DK815-10 cyl 1735 alt 2 hd 15 sec 67>
xtc0 at vme16d16 0xee60 vec 0x64 
xt0 at xtc0 slave 0
zs0 at obio 0xf1000000 pri 6 
zs1 at obio 0xf0000000 pri 6 
ie0 at obio 0xf6000000 pri 6 
ie1 at vme24d16 0xe88000 vec 0x75 
bwtwo0 at obio 0xfd000000 pri 8 
bwtwo0: resolution 1600 x 1280
root on xy0a fstype 4.2
swap on xy0b fstype spec size 67335K
dump on xy0b fstype spec

Any ideas ?
What are those itrunc messages ?

Thanks in advance
Tom.
-- 
Gorodecki Tom.  National Semiconductor (IC)
6 Maskit st. P.O.B. 3007, Herzlia B,  46 104, Israel
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