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A comment on Performance Improvement with the StringBuilder for C++. Parent comment

Re:Performance Improvement with the StringBuilder for C++ by gngeal on Friday September 06, 2013 @10:37AM (#6340637)
String concatenation? Are we living in the 1980's? What about string trees? These problems can be solved simply using a proper data structure. Concatenation, insertion, deletion etc. should be almost constant-time operations.
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Re:Performance Improvement with the StringBuilder for C++ by alayne on Friday September 06, 2013 @10:39AM (#6340643)
Data structures like ropes are really more for editing than concatenation.
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Re:Performance Improvement with the StringBuilder for C++ by phaemon on Friday September 06, 2013 @11:29AM (#6340897)
I'd never heard of "ropes" in that context and read that as the worst simile ever ("Data structures, like ropes, are...")
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Re:Performance Improvement with the StringBuilder for C++ by lucian1900 on Friday September 06, 2013 @11:26AM (#6340883)
Trees (like the ropes you might use in this case) are not necessarily faster on modern CPUs. Caches and branch prediction tend to dominate performance in such cases.
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Re:Performance Improvement with the StringBuilder for C++ by gngeal on Friday September 06, 2013 @02:49PM (#6341997)
I don't see how branch prediction and caches could dominate performance of logically concatenating a huge amount of text instead of doing it physically.
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Re:Performance Improvement with the StringBuilder for C++ by dkersten on Friday September 06, 2013 @03:16PM (#6342119)
I guess it depends on what other operations you need. If the only operation you need is concatenation then trees are definitely faster. Otherwise it depends.
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Re:Performance Improvement with the StringBuilder for C++ by lucian1900 on Saturday September 07, 2013 @01:45PM (#6345789)
Arrays and copies are often faster than the equivalent structure-sharing trees, under a certain size at least.
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