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2021-12-22Remove CPU lockingEelco Dolstra
This was already accidentally disabled in ba87b08. It also no longer appears to be beneficial, and in fact slow things down, e.g. when evaluating a NixOS system configuration: elapsed time: median = 3.8170 mean = 3.8202 stddev = 0.0195 min = 3.7894 max = 3.8600 [rejected, p=0.00000, Δ=0.36929±0.02513]
2013-08-07Run the daemon worker on the same CPU as the clientEelco Dolstra
On a system with multiple CPUs, running Nix operations through the daemon is significantly slower than "direct" mode: $ NIX_REMOTE= nix-instantiate '<nixos>' -A system real 0m0.974s user 0m0.875s sys 0m0.088s $ NIX_REMOTE=daemon nix-instantiate '<nixos>' -A system real 0m2.118s user 0m1.463s sys 0m0.218s The main reason seems to be that the client and the worker get moved to a different CPU after every call to the worker. This patch adds a hack to lock them to the same CPU. With this, the overhead of going through the daemon is very small: $ NIX_REMOTE=daemon nix-instantiate '<nixos>' -A system real 0m1.074s user 0m0.809s sys 0m0.098s