diff options
author | Ben Noordhuis <info@bnoordhuis.nl> | 2014-12-19 23:46:37 +0100 |
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committer | Ben Noordhuis <info@bnoordhuis.nl> | 2014-12-20 21:33:52 +0100 |
commit | aff56cd2b4fb26157ee55cc9377d5186e5625f32 (patch) | |
tree | d677cfb3ef41279bd0bea03ac49c5c6ca2496c9d | |
parent | 6b2af5f0c7056fc8ab35633b45d6346ab2fdc4f5 (diff) | |
download | android-node-v8-aff56cd2b4fb26157ee55cc9377d5186e5625f32.tar.gz android-node-v8-aff56cd2b4fb26157ee55cc9377d5186e5625f32.tar.bz2 android-node-v8-aff56cd2b4fb26157ee55cc9377d5186e5625f32.zip |
lib: micro-optimize url.resolve()
Replace the call to Array#splice() with a faster open-coded version
that creates less garbage.
Add a new benchmark to prove it. With the change applied, it scores
about 5% higher and that is nothing to sneeze at.
PR-URL: https://github.com/iojs/io.js/pull/184
Reviewed-By: Chris Dickinson <christopher.s.dickinson@gmail.com>
-rw-r--r-- | benchmark/url/url-resolve.js | 31 | ||||
-rw-r--r-- | lib/url.js | 13 |
2 files changed, 41 insertions, 3 deletions
diff --git a/benchmark/url/url-resolve.js b/benchmark/url/url-resolve.js new file mode 100644 index 0000000000..5f6c1f7600 --- /dev/null +++ b/benchmark/url/url-resolve.js @@ -0,0 +1,31 @@ +var common = require('../common.js'); +var url = require('url'); +var v8 = require('v8'); + +var bench = common.createBenchmark(main, { + type: ['one'], + n: [1e5], +}); + +function main(conf) { + var type = conf.type; + var n = conf.n | 0; + + var inputs = { + one: ['http://example.com/', '../../../../../etc/passwd'], + }; + var input = inputs[type] || []; + + // Force-optimize url.resolve() so that the benchmark doesn't get + // disrupted by the optimizer kicking in halfway through. + for (var name in inputs) + url.resolve(inputs[name][0], inputs[name][1]); + + v8.setFlagsFromString('--allow_natives_syntax'); + eval('%OptimizeFunctionOnNextCall(url.resolve)'); + + bench.start(); + for (var i = 0; i < n; i += 1) + url.resolve(input[0], input[1]); + bench.end(n); +} diff --git a/lib/url.js b/lib/url.js index 2231ea0ca7..2d9d436a91 100644 --- a/lib/url.js +++ b/lib/url.js @@ -670,12 +670,12 @@ Url.prototype.resolveObject = function(relative) { for (var i = srcPath.length; i >= 0; i--) { last = srcPath[i]; if (last === '.') { - srcPath.splice(i, 1); + spliceOne(srcPath, i); } else if (last === '..') { - srcPath.splice(i, 1); + spliceOne(srcPath, i); up++; } else if (up) { - srcPath.splice(i, 1); + spliceOne(srcPath, i); up--; } } @@ -750,3 +750,10 @@ Url.prototype.parseHost = function() { } if (host) this.hostname = host; }; + +// About 1.5x faster than the two-arg version of Array#splice(). +function spliceOne(list, index) { + for (var i = index, k = i + 1, n = list.length; k < n; i += 1, k += 1) + list[i] = list[k]; + list.pop(); +} |