HP 9000 Server for Informix Database

[Steve Lewis]

I know that 550 PA8600s will seems fast compared with your old K class, but if you want it to last 5 years then you really should go for the PA8700s. This is partly because the cpu upgrade path is difficult from 550 upwards. The 8700s have a higher power requirement which means new PSMs and maybe a new motherboard.
750s are a lot quicker than 550s. We estimated 45% faster.
Dont install any less than 4Gb of RAM. If you really go for the 550s then you ought to buy an external disk controller, such as a VA7110/7410 or xpNNNN.

As a slightly different example of a big informix database. I have a 12-way rp8400 with 12Gb of RAM and 2Tb of disk. I struggle to make it use up more than 50% cpu with 24 concurrent batch processes and 2 large instances. The disks (va7410) supply up to 250000 blocks per second (sar). It really is overkill for our purposes and the 12 875Mhz cpus never all get used. Informix oninits spend more time waiting for mutexes or in kernal calls than processing SQL.

You have been given good advice for the servers and storage i.e rp7400/VA7410 and lots of io slots. I would add that you need 2Gbit fibre to get the most out of the io. SCSI is not recommended for support/part replacement reasons. Lastly don't even think about buying any tape drive slower/smaller than an Ultrium. In 64 bit Ids we get up to 400Gb on a single tape.
One of my N4000s with 4Gb of RAM supports 3 Informix instances with 600 concurrently available databases. Try that with Oracle.

Some application suppliers e.g. SAP give you recommendations on server sizes.

Lastly there are many other threads here on the HP forums to do with performance/planning/sizing which should help you plenty.

[Steve Lewis]

One other thing.
IDS 9.40 is already out and I am using it. It has the big advantage of >2Gb chunk sizes, which IBM call expanded chunk capacity mode; you enable it with an onmode command (why not onconfig?)

It also has LRU cleaning params to 2 decimal places e.g. in the extreme case you could say LRU_MAX_DIRTY 0.02 LRU_MIN_DIRTY 0.01 or whatever, which is good for extremely large LRU/BUFFER combinations.

It also has the SQL statement cache which is a boon for multi-tiered s/w architectures.

If you are migrating to a new machine/storage, then this is a good time to try 9.40.

[David Uraneck]

We moved from K460 for our SAP over Informix 7.30 instance to an rp7410. DON'T get an rp7410 unless you really need the partitioning feature--it's a waste of money! A used N-class (now rp7400) will work just as well and you will get much better value for your money. I know, we just installed a refurbed rp7400 to replace our Q/A machine, and it works fine. Also, the GSP on the rp7410 is much wierd compared to the GSP on the N-class or L-class, and you don't need to call HP field engineers every time you have to deal with it. Keep it simple!

Also, if your DB size is not too large you don't need to go to a fiber fabric SAN. Try to keep it direct connected to your server. Setting up a SAN installation is like a "growth" experience if you are not prepared for what you are getting into. Again, keep it simple--you can always migrate to more complexity when it is required.

Then, most of your peripherals, e.g. DLT tape drives, etc. will not work on rp7400 series which make heavy use of LVD (low voltage SCSI devices). Your HVD (high voltage SCSI) devices will not work here since rp7xx's usually come configured for LVD. Plan on using Ultrium LVD tape drives and have them installed by knowledgable FE's. The LVD cabling and termination can be tricky if you do not know what you are doing.

VA7400 disk arrays take a little getting used to, but are well worth it. Avoid the FC60 disk arrays if you have the funding for the VA7400/7100. They are just easier to administer. We suffered a combo crash of a VA7400 controller and a disk, and I was amazed that it was able to recover--but, it did! A DB restore was not required. It has resilience!

You will be very pleased with the performance improvement in the rp7xxx series compared to your K200 series. By all means pay the extra bucks for the 750MHz CPU's and you will get your 4-5 years use out of them.

[Nick Wickens]

I am in the process of upgrading to Informix 9.3 (although we have just been sent 9.4) and at the same time we are moving from a K370/6 to an RP7410/4 (650Mz) with a VA7410 SAN.

We got an amazing leasing deal from HP via our VAR which was a lot cheaper than purchase and the kits ours at the end of four years anyway !so I would suggest you ask about leasing agreements.