Don't create as many garbage objects during reads - #12
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The old method of reading a row by creating a new reader for every row is quite inefficient because it leaves a lot of objects laying around for the garbage collector. This change creates a CSVParser once and then re-uses it for every row. There's a chance this change causes a regression, because CSVSerde is no longer serializable (CSVParser isn't serializable) but this doesn't seem to be an issue for me in my testing.
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In my preliminary testing, this caused a simple count(*) job of 120-130 sec to go down to 100-110. |
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The old method of reading a row by creating a new reader for every row is
quite inefficient because it leaves a lot of objects laying around for the
garbage collector. This change creates a CSVParser once and then re-uses it
for every row.
There's a chance this change causes a regression, because CSVSerde is no
longer serializable (CSVParser isn't serializable) but this doesn't seem to be
an issue for me in my testing.