forked from lix-project/lix
4ccd48ce24
Evaluation of a NixOS configuration spends quite a lot of time in the "filter" function in Nixpkgs. As implemented in Nixpkgs, this is a O(n^2) operation, so it's a good candidate for providing a more efficient (i.e. primop) implementation. Using it gives a ~10% speed increase and a significant reduction in the number of evaluations. Statistics before (on a NixOS system config): time elapsed: 1.3258 size of a value: 24 environments allocated: 1980939 (50127080 bytes) list elements: 14679308 (117434464 bytes) list concatenations: 50828 values allocated: 2098938 (50374512 bytes) attribute sets allocated: 392040 right-biased unions: 186334 values copied in right-biased unions: 591137 symbols in symbol table: 18271 number of thunks: 1645752 number of thunks avoided: 1921196 number of attr lookups: 430798 number of primop calls: 838807 number of function calls: 1930107 Statistics after: time elapsed: 1.17982 size of a value: 24 environments allocated: 1543334 (39624560 bytes) list elements: 9612638 (76901104 bytes) list concatenations: 37434 values allocated: 1854933 (44518392 bytes) attribute sets allocated: 392040 right-biased unions: 186334 values copied in right-biased unions: 591137 symbols in symbol table: 18272 number of thunks: 1392467 number of thunks avoided: 1507311 number of attr lookups: 430801 number of primop calls: 691600 number of function calls: 1492502 |
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.. | ||
attr-path.cc | ||
attr-path.hh | ||
common-opts.cc | ||
common-opts.hh | ||
eval-inline.hh | ||
eval.cc | ||
eval.hh | ||
get-drvs.cc | ||
get-drvs.hh | ||
lexer.l | ||
Makefile.am | ||
names.cc | ||
names.hh | ||
nix.sdf | ||
nixexpr.cc | ||
nixexpr.hh | ||
parser.y | ||
primops.cc | ||
symbol-table.hh | ||
value-to-xml.cc | ||
value-to-xml.hh | ||
value.hh |