no, its stoped between 2 and 3 GB only.
there is TB sized image file on the same partition...
With that being the case then I agree with you about a corruption or disk I/O error causing the issue, which will have to be repaired prior to you completing the indexing operation.
On a side note due the massive count of files you are trying to index, a website search can take a while going through a text file. So it went ahead and made a mysql schema and bash script that can be used for an introductory indexing, it takes a while but can be beneficial. The benefits you can get from database indexing would be querying of searches and the ability to code the site to automatically update any new files or deleted files from the database.
Again my script can take a while, but if you are interested I can post the script here.