标签：hba raid controller ssd hdd
Neil Cameron
客户通常对端口数目有着确定的想法。我感到这一点有些不同寻常，原因是人们常常对生活中的其他事情并无此定见。但是，说到RAID或HBA控制器上的端口数目，大家确实有着十分固定的看法。
举个例子：我有两个SSD——哦，你没有两个端口的控制器，那我就看看四个端口的吧。但我无论如何也不会考虑16个端口的控制器，因为我的思维已经卡在我当前拥有的硬盘数目上。遗憾的是，事实上，不管你眼下能否意识得到，你所需要的其实是16端口的控制器。
下文还会再回过头来讨论这个问题。现在，先让我们将生活中对其他事情的态度与对RAID控制器的做个比较。我居住的国家（澳大利亚）里的限速（在高速公路上）是110公里/小时。那么，我为什么需要一辆行驶速度超过110公里/小时的摩托车呢？我究竟为什么要买一架能跑道265公里/小时的Ducati Monster呢？
再看一件事。
我最近刚刚升高了我的四驱车上的底盘——我有几个选择：采用标准的高度、加高30mm或者60mm。唔，由于多数时候我还是在路面上行驶的，所以我完全可以就用标准的高度，但你猜怎么着——我太太现在需要梯凳才能上车了，因为我给它加高了60mm。
所以，涉及到我的座驾，看起来我对法律规定亦或是常识所要求的限制都没有什么固见，但当问题是选择RAID卡时，我确实也有我的固定见解（正如多数客户一样）。
你猜着了——我又在喋喋不休地宣传PMC的71605E——一款16端口的“入门级”控制卡，高速、高性能、价格也可算低廉，对于SSD（或者HDD）组成的RAID 10阵列绝对是完美选择。但有客户认真研究过该产品么？答案是否定的。因为此卡支持的端口数目为16，而客户的脑筋已经固定在4端口或8端口的控制器上。看来，我选择的座驾都是为了充分满足我的需求，而非依照法律或我太太的身高所决定的指标来购置。这不恰恰应该是我们选择控制器的方式么？——到底什么能符合我的“性能”需求，而不是我的“数字”上的要求。
如果PMC的营销部门总部在澳大利亚，我们就可以发布一条广告，大标题为“谁关心***有多少端口？“虽然这只是个幻想，但话说到底，这正是需要深深镌刻在客户的思维模式当中的——不要再考虑拥有的硬盘数目，转而着手考虑到底哪一款控制器拥有足够的处理性能，能够满足你的需求。此番讨论主要针对的是SSD用户，因为他们已经下决心采用了更为快速的设备，但还未能改变选择控制卡的思维方式——而改变已经迫在眉睫。
再次回到我的摩托车的类比….我可以买廉价的轮胎，也可以买贵得离谱且远远超出我的驾驶能力的Pirelli轮胎——猜猜我买的是什么（肯定不是廉价、破烂的）——我想让我的摩托车具备跑到其极至性能的能力——尽管它的主人已经不复当日雄风。
所以，别再想端口数了….好好考虑考虑性能吧（PMC的7系列和8系列产品）。
Here goes with another controversial blog forProduct Marketing to ponder …
Customers have a fixation on port numbers. Ifind it a bit unusual because we tend not to have the same sort of fixation onanything else we do in life. However when it comes to port count on RAIDcontrollers or HBA’s we definitely have a fixation.
Example:I have 2 x SSD – hmm, you don’t have a 2-port controller so I”ll look at 4-portinstead. I’ll never even think about looking at 16 port controllers because I’mfixated on the number of drives I currently have. That’s a shame because infact it’s the 16-port controller that you need, whether you currently recogniseit or not.
I’ll come back to that but let’s look at the rest of our life compared to RAIDcontrollers. The speed limit in my country (on the open motorway) is 110km/h.So therefore why do I need a motorbike that does more than 110km/h?
Why onearth would I own a Ducati Monster that’s capable of around 265km/h (don’t tellthe wife that).
OR
I recently upgraded the suspension on my 4WD– I could have standard height, 30mm lift or 60mm lift? Hmmm, I mostly drive onthe road so I could stick with the standard height, but guess what – the wifenow needs a step ladder to get into the car because it’s had the 60mm lift
SoI have no fixation on the limits imposed by the law, or the limits imposed by common-sense when it comes to my vehicles, but I certainly have one (as do most customers) when it comes to choosing RAID cards.
You guessed it – I’m banging on about the71605E again – a 16 port “entry” card that is absolutely perfect for RAID 10 onSSD (or HDD for that matter) – fast, capable and cheap(ish). But do customer sever look at it?
No, because it’s 16 ports and they arefixated on 4 and 8 port controllers. So I own the vehicles that suit my needs,not vehicles that are dictated to me by random numbers imposed by the law or mywife’s height. Funny enough that’s the way we should look at controllers – what suits my “performance” requirements, not what suits my “numbers” requirements.
If our marketing department was based in Australia we’d run an ad campaignentitled: “who gives a *^%&$ how many ports the thing has?”. Can’t reallysee that ever happening in this company, but at the end of the day that’s what needs to be embedded in customer mindsets – stop thinking about the number of drives you have, and start thinking about what controller has the processing performance to handle your requirements. This is mostly addressed at SSD users because while they have made up their mind to use a faster device, they still haven’t changed their mindset about which controller card they should use– and they need to big time.
Using my bike as analogy again … I can buy cheap tyres, or I can buy ridiculously expensive Pirelli’s that are far more capable than my riding ability – and guess what I buy (certainly not the cheap and nasty) – I want to give my bikethe ability to perform to it’s full potential – even if the rider isn’t as capable as he once was.
So stop thinking port count … and start thinking performance (7 and 8 series).
标签：hba raid controller ssd hdd
原文地址：http://blog.csdn.net/pmc/article/details/44238193
