In 64-bit 184.108.40.206, I have a 2.7MB file of ~4500 CREATE TABLE statements, generated by Toad, each CREATE on one line, with blank lines removed. I replaced " NOCACHE" with " PCTFREE 0 NOCACHE" and it took 07:30 on my Core i7 3720QM laptop w/16GB RAM running Win7 SP1 64-bit.
The only thing I noticed is that the horizontal scroll widget goes a little nuts at the start of the replace, then Toad stops responding and 1 CPU core goes to 100% for the 7+ minutes. The same replace in the same file in v220.127.116.11 still stops responding after a bit and takes 23 seconds, but that’s at least somewhat reasonable. I saw thread http://www.toadworld.com/products/toad-for-oracle/toad_for_oracle_beta_program/f/86/t/23756.aspx but I’m still seeing those symptoms.
I’m thinking this should be easily replicated (hopefully?), but if not, I can probably forge one.