Optimize ConvertToBytes by avoiding unnecessary string <-> bytes conversions and copies. #2932
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max-hoffman
approved these changes
Apr 10, 2025
| func UnquoteBytes(b []byte) ([]byte, error) { | ||
| outIdx := 0 | ||
| for i := 0; i < len(b); i++ { | ||
| if b[i] == '\\' { |
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huh, didn't realize \\ was a single char
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You got to escape the backslash character. '\' would be escaping the closing quote.
This was referenced Apr 11, 2025
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ConvertToBytes is a commonly called function to get the string representation of a value. However, it has some unnecessary allocations where a child function allocates a byte buffer, only for the result to be copied into the buffer provided by the parent function. In other places we needlessly round-trip between string and []byte.
This PR improves performance by removing some of these unneeded copies. In places where ConvertToBytes calls a function that allocates a buffer (instead of using the buffer that ConvertToBytes can provide), we can optimize by using the returned value without copying it again.
Dolt shows a 7% improvement in the
types_table_scanbenchmark.We can potentially do even better by allowing these child functions to take a buffer, removing the need for an extra allocation.