The first read probably does 2 disk seeks (one to find out where the file is, one to red the file). The time for a disk seek is set by the rotation speed of your hard drive.

When it does the first read it caches more of the file "just in case". So when you read the rest you're reading from cache, which is fast.

In reply to Re: Reading files too slow by tilly
in thread Reading files too slow by Anonymous Monk

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