parseTime is 20x slower than an attoparsec parser

[parsonsmatt]

cf byteverse/chronos#18 (comment)

Currently mysql-simple uses parseTime to parse the time. Using a custom attoparsec parser would make things faster and more memory efficient.

[paul-rouse]

Chronos is interesting! Do you think the overall gain would be significant, in the context of the whole processing of a result?

[parsonsmatt]

That's the important question :) I'll have to write a benchmark for it! Someone on FPChat mentioned that parsing UTCTime out of a database query was taking 20% of the runtime of his app, which got me on this chase.