Optimize ExtractXML() calls by avoiding unnecessary string copies #1419
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| string::size_type loc_end = XMLdata.find( key_end, loc+3); | ||
| if (loc_end != string::npos ) | ||
| { | ||
| extraction = XMLdata.substr(loc+(key.length()),loc_end-loc-(key.length())); |
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...and one unnecessary move operation 🙂
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Interesting. In the original scraper prototype, where Paul had defined this locally in scraper.cpp (see https://github.com/gridcoin-community/ScraperProxy/blob/master/scraper.cpp), he appropriately made changes to passing the arguments by reference, but maintained the intermediate variable.
This was lost when I fully developed the scraper and then used the already provided ExtractXML calls.
I agree with not using the intermediate variable, as readability is not impacted for something so simple, and given the frequency this is used, results in a good optimization.
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The const ref parameter is good optimization. |
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@tomasbrod I agree--it's insignificant after everything else. I was just being silly 🙂 I find the code just a tiny bit easier to read without it, though. |
Added: - Replace NeuralNetwork with portable C++ scraper #1387 (@jamescowens, @tomasbrod, @Cycy, @TheCharlatan, @denravonska). - Allow compile flags to be used for depends #1423 (@G-UK). - Add stake splitting and side staking info to getmininginfo #1424 (@jamescowens). - Add freedesktop.org desktop file and icon set #1438 (@a123b). Changed: - Disable Qt for windows Travis builds #1276 (@TheCharlatan). - Replace use of AppCache PROJECT section with strongly-typed structures #1415 (@cyrossignol). - Change dumpwallet to use appropriate data directory #1416 (@jamescowens). - Optimize ExtractXML() calls by avoiding unnecessary string copies #1419 (@cyrossignol). - Change signature of IsLockTimeWithinMinutes #1422 (@jamescowens). - Restore old poll output for getmininginfo RPC #1437 (@a123b). - Prevent segfault when using rpc savescraperfilemanifest #1439 (@jamescowens). - Improve miner status messages for ineligible staking balances #1447 (@cyrossignol). - Enhance scraper log archiving #1449 (@jamescowens). Fixed: - Re-enable full GUI 32-bit Windows builds - part of #1387 (@jamescowens). - Re-activate Windows Installer #1409 (@TheCharlatan). - Fix Depends and Travis build issues for ARM #1417 (@jamescowens). - Fix syncupdate icons #1421 (@jamescowens). - Fix potential BOINC crash when reading projects #1426 (@cyrossignol). - Fix freeze when unlocking wallet #1428 (@denravonska). - Fix RPC after high priority alert #1432 (@denravonska). - Fix missing poll in GUI when most recent poll expired #1455 (@cyrossignol). Removed: - Remove old, rudimentary side staking implementation #1381 (@denravonska). - Remove auto unlock #1402 (@denravonska). - Remove superblock forwarding #1430 (@denravonska).
Low-hanging fruit: calls to
ExtractXML()passed input by value, which results in a at least one extra copy operation per invocation. The application uses this function everywhere, so we can reduce a little bit of overhead by passing references.Also, this removes the forward declaration from files that don't use it.