ia64 "hello world" success; crfsd receives SEGV under heavier load

[Alex Chiang]

* Zach Brown <zach.brown at oracle.com>:
> 
> > #3  0x2000000000084180 in __assert_fail () from /lib/tls/libc.so.6.1
> 
> >     at crfsd/update.c:868
> 
> I think I fixed this:
> 
>   http://oss.oracle.com/mercurial/zab/crfs/rev/f163aed9f781
> 
> The log showed that right before the assertion failure we split a child
> and took up the last block pointer slot in the parent.  The assertion
> didn't take this case into account.

Thanks, this patch helped. I can now cp a linux kernel tree
across the network using crfs.

Unfortunately, it looks like there *might* be some data
corruption (haven't gotten around to verifying it yet). I say
*might* based on this experiment:

[root at canola ~]# cp -R linux-2.6 /mnt/crfs/

[root at canola ~]# cp -R /mnt/crfs/linux-2.6 ./linux-2.6-from-crfs-mnt

[root at canola ~]# tar cvf linux-2.6.tar linux-2.6

[root at canola ~]# tar cvf linux-2.6-from-crfs-mnt.tar linux-2.6-from-crfs-mnt

[root at canola ~]# cksum linux-2.6.tar 
1563756242 2588590080 linux-2.6.tar

[root at canola ~]# cksum linux-2.6-from-crfs-mnt.tar 
3428951535 2588651520 linux-2.6-from-crfs-mnt.tar

[root at canola ~]# du -skx linux-2.6
2704216 linux-2.6

[root at canola ~]# du -skx linux-2.6-from-crfs-mnt
2699280 linux-2.6-from-crfs-mnt

I'm also seeing these messages from the log file:

Apr 03,2008|14:39:49|29576|send_final_neg_errno: assertion 'wire' failed: errno 4294967274

No debug.log for this run (I turned it off to do some timing
tests... :)

[root at canola ~]# time cp -R linux-2.6 /mnt/crfs/

real    12m35.431s
user    0m0.500s
sys     0m36.652s

[root at canola ~]# time rm -rf /mnt/crfs

real    0m4.455s
user    0m0.076s
sys     0m4.380s

For comparison, same tree over NFS:

[root at canola ~]# time cp -R linux-2.6 /mnt/achiang/blender-test/

real    90m26.534s
user    0m0.496s
sys     0m13.224s

[root at canola ~]# time rm -rf /mnt/achiang/blender-test/linux-2.6/

real    18m29.487s
user    0m0.080s
sys     0m2.960s

I'll keep poking. (sometimes, real work gets in the way ;)

Thanks.

/ac