vector deserialization is speeded up a little #1704
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| @@ -23,13 +23,11 @@ namespace hpx { namespace serialization | |||
| ar >> size; //-V128 | |||
| if(size == 0) return; | |||
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| vs.reserve(size); | |||
| vs.resize(size); | |||
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resize() causes the default c-tors of all objects in the vector to run, which can be costly. I don't see how this would lead to a speed-up.
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You can see that for the old version there is already default construction of temporary object inside the loop value_type v; , which later is moved to vector by push_back. This commit is only about avoiding this extra moving by default construction of objects and their deserialization right inside the vector.
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Ah, got it. Totally makes sense. Thanks!
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LGTM, nice catch! This is not only to avoid the move. Especially for non-movable types this saves us a copy operation. |
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@AntonBikineev BTW, nice job on the overall performance of the serialization code: https://github.com/STEllAR-GROUP/cpp-serializers! We should write a blog post about this, somewhere! |
…alization vector deserialization is speeded up a little
The speedup is palpable in cpp-serializers benchmark when serializing strings.