MSSQLSpatial Fix BCP performance problem (#9112) #9113
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| panSRID = (int *)CPLRealloc(panSRID, sizeof(int) * (nKnownSRID + 1)); | ||
| papoSRS = (OGRSpatialReference **)CPLRealloc(papoSRS, sizeof(void *) * |
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I know nothing about this driver, and I see that this is the existing implementation.
But two (!) reallocations for each (!) single SRS doesn't look how I would implement such a cache from scratch today. However, maybe it isn't a bottleneck in the DB context.
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@dg0yt What would be the suggested solution? I don't see a performance issue here, especially because we usually look for only a limited set of SRS-s for each data source (a single one in most cases).
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A std::map<int, std::unique_ptr<OGRSpatialReference>> m_oSRSCache would be the best C++11 replacement for the nKnownSRID, panSRID and papoSRS members.
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Rectification this should be a
std::map<int, std::unique_ptr<OGRSpatialReference, OGRSpatialReferenceReleaser>> m_oSRSCache
so that the free function called is OGRSpatialReference::Release() and not plain delete
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A std::vector<struct> with a reasonable reserve should be fine, thanks to locality.
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cf #9119 for a modernization proposal for the PG driver which uses the same pattern
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