It all depends on what you're doing. An obvious solution would be to use a hash (or HoHoHo..oH) that would keep track of what you've already worked on. You would parse the line, check the cache, and do the actions only if the line wasn't in the cache.

As the other poster said, this is only useful if your actions per line are very expensive. "some simple math" doesn't sound like it would be expensive enough. However, 55% does sound like a potentially signficant savings.

Without Benchmarking, it's impossible to know for certain, but the parsing is often the most expensive part of working with logfiles, not the actions one takes at each point.

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Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.

In reply to Re: Caching process sets by dragonchild
in thread Caching process sets by billyak

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