restore: no memory to extend symbol table

[David King]

When moving from one disk to another, I did a dump of a large  
filesystem, like this:

mkdir ~/tmo && cd ~/tmp && dump -0f - /dev/devicenode | split

So now I have 99G in 100 files named xaa through xdv

However, when I try to restore it:

mount /mountpoint && cat ~/tmp/* | (cd /mountpoint && restore -rf -)

after cat spits out 2.18 GB (in the same spot every time), after  
restore creates a number of directories (but no files), I get the error:

no memory to extend symbol table
abort? [yn]

I've seen two other posts about similar errors:
<http://groups.google.com/group/fa.freebsd.questions/browse_frm/ 
thread/c6fb6245f3f010dc/3b7762d8e1410102?lnk=st&q=%22no+memory+to 
+extend+symbol+table%22&rnum=5#3b7762d8e1410102>
<http://groups.google.com/group/info.bsdi.users/browse_frm/thread/ 
4b547bccf96807bb/bb08c14f7aa4a5e6?lnk=st&q=%22no+memory+to+extend 
+symbol+table%22&rnum=4#bb08c14f7aa4a5e6>

I'm sure that I have enough space on /tmp (since I symlinked it to a  
directory on a large disk), which is one proposed fix. Another  
proposed fix is to allow restore to get more than 512MB of RAM, but  
I'm not sure where to set that (since I'm not familiar with vm and I  
have no such limit in /etc/login.conf, and can find nothing in  
sysctl). It's not a RAM limit, because I have 1GB of RAM and 2.5 GB  
of swap.

The other proposed fix is to use interactive mode and restore less at  
a time, but if I do that hardlinks between directories may be broken  
and I need to retain those (unless they wouldn't be broken between  
successive restores, in which case I can do that).

Any ideas?

I'm running 6.2-RELEASE

-- David