GH-41: BaseVariableWidthViewVector setZero only if necessary#557
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lidavidm merged 2 commits intoapache:mainfrom Jan 27, 2025
Merged
GH-41: BaseVariableWidthViewVector setZero only if necessary#557lidavidm merged 2 commits intoapache:mainfrom
lidavidm merged 2 commits intoapache:mainfrom
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lidavidm
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Jan 24, 2025
| if (length <= INLINE_SIZE) { | ||
| // to clear the memory segment of view being written to | ||
| // if it has been set | ||
| if (viewBuffer.getLong(writePosition) != 0 || viewBuffer.getLong(writePosition + 8) != 0) { |
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So the basic effect is that if the view buffer is all 0, we skip setting it back to 0? And basically, for freshly allocated memory, this skips a redundant memset? Can we explain it a little more in the comment?
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Yes, it's redundant to setZero if the data is already zero. Checking will introduce some overhead, but it is much smaller than that of setMemory.
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Is it safe to check only these positions? IIUC, ZERO is a valid value to be set.
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But if all 16 bytes are 0, there is no need to set them to 0 again, I think is the point.
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Closes #41.