ranonymize too slow?

[Christos Papadopoulos]

Hi folks,

I am trying to use ranonymize for some large argus files. This is useful 
for us because we want to share some argus data with fellow researchers, 
but anonymize them to protect the innocent.

The file I am trying to anonymize is large, about 18GB compressed. As 
you can imagine, there are millions of flows in there.

I only want IP address anonymization, so I turned everything else off in 
the ranonymize.conf file.

Well, ranonymize has been running for almost 3 hours with about 1/20th 
of the file done. It is using 100% of a CPU, but only 4% of memory in a 
32GB machine. Clearly it's not a memory or swap issue.

I can't figure out why it's taking so long. I thought it would be almost 
as fast as reading and writing the file plus some time to 
compress/decompress and some time for checking the hash for the 
anonymized addresses.

Any idea what's pounding the CPU and slowing it down? I can investigate 
further by profiling the code, but thought I throw the question out 
there first in case someone else has done it.

Thanks!

Christos.