Hi SimonPratt,

although I have expressed some disagreement, I also upvoted both your posts, because I understand your point.

I disagree however, with the idea that profiling is never a bad idea.
That's not what I said. Well, not quite. ;-) I said "very rarely (well almost never) a bad idea".

But I fully agree with you that, in order to improve code performance, you need a deep understanding of your program, as well as of the programming language you are using and the external resources your are relying on (files, database, network, etc.). But if I see that, say, my program is spending a lot of time in subroutine Y, then I will certainly not only think about how can I make Y faster, but also if I can call Y less often (perhaps by caching some data), or replace Y altogether with something better. Or even possibly change the whole program architecture and/or algorithm, and re-factor the whole shebang, but that of course comes with a higher cost (non regression testing, etc.), but I have done it a few times.

But before stating to do that, I need to ascertain that it is really Y that is guilty. Maybe the problem is somewhere else.

In reply to Re^5: How to optimise " csv into mysql " using TEXT:CSV_XS and DBD::Mysql by Laurent_R
in thread How to optimise " csv into mysql " using Text:CSV_XS and DBD::Mysql by taiko

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