no dump, not enough free space on device

[Randy Bush]

stable of march 7, but this has been a long-term problem on
this system

system has 1g of real memory

real memory  = 1073217536 (1023 MB)
avail memory = 1044914176 (996 MB)

2g of swap

# swapinfo
Device          1024-blocks     Used    Avail Capacity
/dev/twed0s1b       2097152     1428  2095724     0%

has it set up to save disk flowers

dumpdev="/dev/twed0s1b" # Device name to crashdump to (or NO).
dumpdir="/var/crash"    # Directory where crash dumps are to be stored

but

savecore: reboot after panic: ffs_blkfree: freeing free block
savecore: no dump, not enough free space on device (663614 available, need 1048066)
savecore: unsaved dumps found but not saved

randy