I working on a study where we bring in nearly a Gb of XML data each day, parse it and put it into MySQL for various academics to pore over. It takes 4-6 hours to get all the bits downloaded from the places its collected at and parsed. This level will rise 3-5 fold over the next year.

I recently took over / inherited the code for this and found that its running only a single thread - sequentially read, parse, repeat. I have two boxes for this job - the db machine and the read / parse machine. Both are 8-way with 8Gb of RAM.

My questions are thus:
1) how well do DBI and DBD react to being threaded?
2) does DBI use row locking or table locking when 'AutoCommit = 0' is used? (the tables in question are InnoDB)
3) would threading this process gain me anything or should I be happy with its current (functional) condition?

Suggestions are appreciated.

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