最近在 appium 1.5.3 上运行 IOS case 时，在执行命令时，经常会遇到卡顿现象，性能如此之差，一直没找到解决方案，望走过路过的各位大神给指点下，如何解决。
比如，命令都由 UIAuto 发给 instruments 了，但是在 instruments 执行时，就一直卡在这里，特别影响 case 的运行，
想请教下各位大仙，这种情况如何解决？

[MJSONWP] Calling AppiumDriver.performMultiAction() with args: [[[{"action":"press","optio...
[debug] [iOS] Executing iOS command 'performMultiAction'
[debug] [UIAuto] Sending command to instruments: target.touch([{"time":0.2,"touch":[{"x":73,"y":320},{"x":73,"y":285},{"x":298,"y":320},{"x":298,"y":285},{"x":185,"y":301}]}])
[debug] [Instruments] [INST] 2017-04-13 10:00:05 +0000 Debug: evaluation finished
[debug] [Instruments] [INST] 2017-04-13 10:00:05 +0000 Debug: responding with:
[debug] [Instruments] [INST] 2017-04-13 10:00:05 +0000 Debug: Running system command #8: /usr/local/Cellar/node/6.3.0/bin/node /usr/local/lib/node_modules/appium/node_modules/appium-ios-driver/node_modules/appium-uiauto/build/lib/bin/command-proxy-client.js /var/folders/sq/9tbj9l214qsfnjb1qh9x_nrr0000gn/T/instruments_sock 2,{"status":0,"value":""}…