HP slaps P9500 label on HDS' VSP array

Misleading

Having extensive experience of these things, the only way that you can scale and XP24K out to 2.26PB is to use 2TB FATA drives. Putting those in an enterprise array of this type is not, generally, a great idea. The reason for this is that they are first of all they support very low IOP ratings - half that of a 15K drive. This is compounded by being 4 times larger so the access density is 8 times worse. that the 500GB 15K drives. It gets worse - they HP documentation on these FATA drives state that they can only be used for random IO patterns 30% of the time, or you suffer abnormally high failure rates. Take that at face value, and you have only about 2% of the access density per GB on the FATA drives compared to enterprise for random IOPs (and actually managing the IO access pattern on a huge, shared enterprise array is a tricky thing to do).

If you want (relatively) low access rates on large amounts of data, then it's generally more cost effective to put those disks into an EVA8400 or the like. However, take that duty cycle seriously and be very careful what you use those FATA drives for. Bear in mind that it can take the best part of 24 hours to rebuild a RAID-5 set with 2TB drives (the only way you can max the usable storage) and, all that time, you are vulnerable to a second failure.

ftp://ftp.compaq.com/pub/products/storageworks/whitepapers/5982-7353EN.pdf

I do not know anybody who has maxed out and XP24K with FATA drives, and they would be mad to do so. If you use 600GB 15K drives in an XP24K then the total capacity is not much different to the P5000 and it occupies much less space and uses less power per GB for equivalent capacity and IOP count. If you need more than one chassis, buy a second one.

On any case, it is possible to use those EVAs and larger, slower disks as back-ends to boost the apparent capacity of the array.

Enterprise Arrays are not just about the absolute amount of disk capacity you can put in a box. In fact I would argue that isn't even in the top two or three priorities. First is data security and second is interruptible availability. Connect a few hundred servers to these things and you might as well pull the power supply in your data centre. Then there is maintaining high levels of reliable throughput and low latency on a mixed and changing workload so that when your data warehouse kicks in it doesn't screw up the response time in your call centres. Then you need those added value services - snapshots, array replication. Then you need capacity scalability, but you can (usually) always achieve that, with some compromises, by mapping across multiple arrays (the compromises are about ease of data migration and some array based async replication tools - and some manufacturer's arrays can cope with that). That dealt with, give me two smaller arrays with lower total power consumption and higher IOP count any time than the same capacity with some sub-enterprise disks.

Incidentally, as far as front-end FC interfaces go, there is not an Enterprise array manufactured which can approach the total bandwidth. That's a fact - all these large arrays run out of puff long before they can saturate all that FC capacity. The difficult bit is to balance the damned things so that you don't get hot spots in the SAN fabric, controllers or individual FCs.

So there is a lot more to what makes an enterprise array than the statistic of how many GB you can stuff into it, and a well-designed array will allow you to scale sideways.

And theres more....

Unfortunately the blades used in the PSP aren't HP but Hitachi ones and are a custom build so no C-class type infrastructure in there. HP tell me the costs will be similar to previous gens in most cases although the entry point will be much lower.

I don't think 3Par can do all an XP can do (yet) or with the credibility in the market place for those real mission critical installations. But I confess I'm largely ingnorant on 3Pars capabilities but excited to understand what they can bring to the party.

Also contrast the Reg article on the HP launch vs HDS's - note the same disparaging comments about whether VSP is fit to lace USP's boots are nowhere to be seen.

Hidden agenda's methinks??