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OverviewAnalysis of 48,438 functions across stable-diffusion.cpp reveals mixed performance impacts from a single architectural commit introducing OptionFlags and refactoring JSON serialization. Modified: 204 functions; New: 131; Removed: 45; Unchanged: 48,058. Binaries analyzed:
Power consumption increases remain under 1%, indicating maintained energy efficiency. Function AnalysisSDGenerationParams::from_json_str (build.bin.sd-server) shows exceptional improvement: response time decreased 1,522,872 ns (34.4% faster: 4,428,253 ns → 2,905,380 ns), throughput time decreased 507 ns (77.7% faster: 652 ns → 145 ns). The refactoring replaced ~95 lines of manual JSON field deserialization with template-based std::_Hashtable::end for CacheDitConditionState (build.bin.sd-server) regressed significantly: response time increased 162 ns (138.5%: 117 ns → 280 ns), throughput time increased 162 ns (194.6%: 83 ns → 245 ns). Despite no source changes, this cache validation function shows compiler optimization failure. Called during DiT condition caching in inference paths, though absolute impact remains minimal (<0.001% of typical inference time). Standard library improvements: Multiple iterator functions ( Other analyzed functions (make_move_iterator, json::create, shared_ptr operations) showed compiler-driven changes in standard library code with minimal real-world impact on initialization paths. Additional FindingsThe commit focused on architectural improvements (eliminating code duplication, network-aware serialization) rather than performance optimization. No GPU operations or ML inference kernels were modified. The JSON parsing improvement directly benefits server deployments, while cache hashtable regression has negligible impact given its sub-microsecond absolute time relative to multi-second inference operations. Compiler version differences (likely GCC 13) drove most performance variations in standard library template instantiations. 🔎 Full breakdown: Loci Inspector. |
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Source pull request: leejet/stable-diffusion.cpp#1277
This PR adds the functionality necessary to convert generic option param types to and from json using the ArgOptions. To achieve this, it adds a number of features:
OptionFlagsto all of the Option types. This implements the ability to mark options as assigned during command line parsing, making it easier to iterate through options manually set by the caller. This also adds a no network tag to mark options that are not meant to be transferred over the network.options_to_jsonandoptions_from_json. These are designed to be generic, able to take an option parameter class and it's corresponding parsed ArgOptions. Theto_jsonvariant makes use of the assigned flag to only focus on parameters that were specifically declared by the caller. These functions operate on all of the basic ArgOptions types dynamically, converting the long_name into a json friendly expression matching the oldto_json_strformatting (underscores instead of dashes). To use this function with an option parameter class, it will need to implementmanual_options_to_json(std::vector<ManualOptions> const&, json&)andmanual_options_from_json(std::vector<ManualOptions>&, json const&)to finalize the conversion for the manual options.SDGenerationParams, as these are the parameters that are most relevant for network transfer to/from the client and server. I also addedjson to_json(ArgOptions const&)andvoid from_json(json const&)convenience methods.