My first reaction is that I'd use 3 threads.

  1. Reads the file and feeds Q1.(Thread::Queue)
  2. Reads Q1, processes the records and feeds Q2 with the data for updating the DB.
  3. Reads Q2, and fires off the updates.

I'd use a high/low water marking system to allow threads to yield their timeslices once the queue they were feeding moved above the high water mark, until it dropped back to the low watermark. Reading threads would yield when their input queues dropped below low water.

Then run some benchmarks to establish the best values for the watermarks.

Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"Think for yourself!" - Abigail

In reply to Re: faster with threads? by BrowserUk
in thread faster with threads? by js1

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