Changed the '_lines' data structure from Appender to built-in array, as the former leaks memory #227
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…as the former leaks memory
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The pseudo-benchmark code that I wrote import std.array;
import std.random;
void main()
{
//Appender!(string[]) arr;
string[] arr;
int n = 1_000_000;
for (int i = 0; i < n; ++i)
{
string s;
for (int j = 0; j < 20; ++j)
{
char c = cast(char) rndGen.front;
rndGen.popFront();
s ~= c;
}
arr ~= s;
}
}I felt that using random and |
Owner
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The performance considerations need to be measured with real-world usage in dpp, not in an external micro benchmark. The reason it's an appender in the first place is because of how long it was taking to process Python.h. I suggest measuring how it affects performance by running dpp on a single-line dpp file with |
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We perhaps should fix Appender ! |
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For example, when translating kernel header files, memory usage for d++ reached 6-7GB on an 8GB machine (and we no longer could spawn a process for CPP to preprocess the .tmp file).
After seeing this issue, I changed from Appender to built-in array type and got a max RAM usage of 2GB (and CPP ran successfully).
Regarding performance, Edi ran some tests and saw no major difference between the Appender and the built-in array (test done on 1 million 20 char-long strings being appended, Appender being faster by 20ms).