Script Speed vs Memory Usage
- by Doug Neiner
I am working on an image generation script in PHP and have gotten it working two ways. One way is slow but uses a limited amount of memory, the second is much faster, but uses 6x the memory . There is no leakage in either script (as far as I can tell).
In a limited benchmark, here is how they performed:
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METHOD  | TOTAL TIME | PEAK MEMORY |  IMAGES
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One     |     65.626 |     540,036 |     200
Two     |     20.207 |   3,269,600 |     200
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And here is the average of the previous numbers (if you don't want to do your own math):
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METHOD  | TOTAL TIME | PEAK MEMORY |  IMAGES
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One     |      0.328 |     540,036 |       1
Two     |      0.101 |   3,269,600 |       1
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Which method should I use and why?
I anticipate this being used by a high volume of users, with each user making 10-20 requests to this script during a normal visit. 
I am leaning toward the faster method because though it uses more memory, it is for a 1/3 of the time and would reduce the number of concurrent requests.