从一台32核CPU,30G内存，800M硬盘的机器上。迁往到双节点RAC机器上，该机器每个节点8核CPU 是双核*4.硬盘和内存没什么变。 听起来是迁往一台高性能机器上，很令人兴奋不已，双节点哦！ 实际上效果并非如此，其中一个节点被另外个数据库所占用，也就是那台节
从一台32核CPU,30G内存，800M硬盘的机器上。迁往到双节点RAC机器上，该机器每个节点8核CPU 是双核*4.硬盘和内存没什么变。
听起来是迁往一台高性能机器上，很令人兴奋不已，双节点哦！
实际上效果并非如此，其中一个节点被另外个数据库所占用，也就是那台节点基本上不能全力去工作，相当于单节点。反而承担多节点管理工作！
UNDO和TEMP 采用两个来切换，而且每个比原来的小上10G。原来都32GUNDO和32GTEMP。
其中暴露出一些存储过程的SQL性能问题，比如占用太多的UNDO,TEMP和DB FILE SEQUENCE READ。
知道LEFT JOIN , MEGR INSERT 比 DELTET 和INSERT INTO 慢些，可数据很可靠!
老大原本想花三天迁移完的，实际上用了9天的时间。主要是发现存储过程中语句业务逻辑缺失些数据，没有完全从其他库上获得完整。
找这个问题所在，用老办法全量从源库 insert into xxxx@tooldb，或者从业务库再次全托。
搞这事真累！ 很多事觉得做的很白费，瞎折腾。民营企业都这德性，中层或者高层下达工作指令时候都是交给你任务，马上就问什么时候完成。
你回答一个时间，他不满意，就说这个时间太长了，就说出他的希望的时间，基本上是在你的时间上缩短50%-80%。你跟他争一点，他就说你态度不好！他说这个工作很紧只有几个星期时间。
其实他们想得比较简单，这工作就这么几下，分分钟的事情；或者以他的技术能力速度来考虑；或者他想不到干这事中会遇到技术和业务问题；或者他没想到你除了干这事，还要干其他的事，被其他琐事的事干扰！
民营企业 强调的是执行力，沟通能力，主动能力，人的主观能动性，乐观向上积极奉献。
反过来想，民企企业创业时一无所有，或者少有的条件，只有靠老板等老大们 发挥自己主观能动性。不过这作风会一直延续下去，并且影响到招人和用人倾向！
想想自己 从中能获得些经验吧！也算是心理安慰，老板也没少给钱，虽然做出来的东西还是被人弃之一边，或者被其他同事重构掉！
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