Edward Grace wrote:
Does the size of the test data set matter? In other words do you notice similar speedups if the test data will all fit in cache?
Wouldn't that give less representative performance results?
I guess it depends what you're trying to represent when measuring the performance. If you're trying to represent the [totally contrived] case of parsing short segments of text that all fit in cache surely it's better?
I was presuming to suggest that the more representative test was that of parsing across the spectrum of possible inputs such code likely will parse in a real finance program rather than contriving small tests to focus on isolated characteristics.
Or is your question more regarding the distribution of the actual values under test rather than the length?
I don't think the lengths will vary much beyond what appears in the test input other than, possibly, the lack of really short inputs.
My suggestion is merely the curiosity of seeing if there is a cache dependent effect or not rather than a 'representative' measurement. I don't for a minute think it's a good idea to permanently modify someone's hard thought through and exhaustive testing.
I was afraid that the test code might be permanently altered and lose sight of what I think is a fairly representative set of test inputs. _____ Rob Stewart robert.stewart@sig.com Software Engineer, Core Software using std::disclaimer; Susquehanna International Group, LLP http://www.sig.com IMPORTANT: The information contained in this email and/or its attachments is confidential. If you are not the intended recipient, please notify the sender immediately by reply and immediately delete this message and all its attachments. Any review, use, reproduction, disclosure or dissemination of this message or any attachment by an unintended recipient is strictly prohibited. Neither this message nor any attachment is intended as or should be construed as an offer, solicitation or recommendation to buy or sell any security or other financial instrument. Neither the sender, his or her employer nor any of their respective affiliates makes any warranties as to the completeness or accuracy of any of the information contained herein or that this message or any of its attachments is free of viruses.