v8是否对单个对象的堆分配有限制?
a = new Array(1024*1024*102)
在节点命令行上失败
FATAL ERROR: JS Allocation failed - process out of memory
此外,当作为脚本运行时,这会失败并出现相同的错误
node --expose-gc --nouse-idle-notification --max-old-space-size=8192
FATAL ERROR: CALL_AND_RETRY_0 Allocation failed - process out of memory
var util = require('util'); o = {}; while(1) { o["hahahahahaha" + String(ctr)] = ctr; ctr++; if (ctr % 100000 === 0) { console.log(util.inspect(process.memoryUsage())); if (ctr % 10000000 === 0) gc(); } }
最后输出:
{ rss: 1009557504, heapTotal: 993408824, heapUsed: 964980592 }
然而,
var a = []; while(1) { var o = {}; o["hahahahahaha" + String(ctr)] = ctr; a.push(o); ctr++; if (ctr % 100000 === 0) { console.log(ctr); console.log(util.inspect(process.memoryUsage())); console.log(); if (ctr % 10000000 === 0) gc(); } }
很好
{ rss: 5466140672, heapTotal: 1091224368, heapUsed: 1070460592 }
编辑:
node -v
v0.10.25
uname -a
Linux 3.13.0-24-generic #47-Ubuntu SMP Fri May 2 23:30:00 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
编辑2:即便如此!似乎v8的限制适用于对象可以拥有的属性数量?
while(1) { if (!o["hahahahahaha" + String(Math.floor(ctr/1000000))]) { o["hahahahahaha" + String(Math.floor(ctr/1000000))] = {}; console.log(Object.keys(o)) } o["hahahahahaha" + String(Math.floor(ctr/1000000))][String(ctr)] = ctr; ctr++; if (ctr % 100000 === 0) { console.log(ctr); console.log(util.inspect(process.memoryUsage())); console.log(); if (ctr % 10000000 === 0) gc(); } }
{ rss: 2474512384, heapTotal: 2466405768, heapUsed: 2431583008 }
另外,我发现了这个:https: //github.com/v8/v8/blob/master/src/objects.h#L2928
我想知道它是否相关.