Ken Ow-Wing's ST 9900 Blog

ST 9900 Guidance: What applications are suitable for virtualization?

Generally speaking, the archival  is key application used when virtualizng devices behind the ST 9900 models such as the ST 9985V and ST 9990V.  A layman view of "archival" in context of this discussion is "old data with less frequent access".
Some examples of this are old e-mails, 2 year year old consumer retail or retail banking transaction data, old medical records.
If you think about it, its data that you don't necessarily need immediately/quickly, but you do need to access it infrequently.

In contrast, if you think about a big retail bank, such as the Bank of America, Citigroup, or Wells Fargo, you need to think about thousands of transactions per second, short block, random read and writes. This is referred to as High Volume OLTP ( Online Transaction Processing).  This is a high performance application, and you would use internal disk in the highest performance configuration you could put togeather.  What you would not do is put this application out on the virtualized external disk.

Now of course there are exceptions to every rule. We do have a few cases of virtualized disk being used for OLTP but the lead systems engineer on the account was very careful to charctreize transaction volume and type and match it to the I/O workload.
Proof of Concepts (POC) in non-production environments where used to test the feasiblity of the application. Let's use an example to illustrate the point. Let's say you have SAP R3 and have an accounting department of 50 people. They may generate in this particular example 50 transactions per hour wth a transaction size of about 30 bytes as they debit and credit A/R (accounts receivables) and A/P (acccounts payable) and G/L (General Ledger). So if you do the math, its not a lot of tranactions. On the other hand, if you were a bank with 815 branches, with an average of 12 tellers per branch, and each transaction takes 2.5 mintues, at 50 bytes each, then the tranaction load increases.

From a technical perspective, the ST 9900 product line is a very cache intensive. So if your application is such that
you have a lot of read hits, then you can get pretty good performance. If not, performance will suffer. If you do a lot a writes, performance may also suffer.

So here is a pointer to the somewhat new Sun PS "Help Desk" and this exerpted to a communication to the ST 9900 field after Americal Sales meeting in Washington DC.

Introducing the "Sun PS Help Desk"

  A)  http://wikihome.sfbay.sun.com/Systems/Wiki.jsp?page=ProfessionalServices

 Please note that it is highly recommended that field sales and SE teams first engage the Sun PS
 Help desk when planning ST 9900 installations. This will improve the success rates in terms of
 customer installations.

 Sun PS offers this help desk to help you during the pre-sales process, and helps get you by the
 awkward period where you don't have a contact yet, but you still need to engage Sun PS.
 I do not represent Sun PS, but do recommend you do talk to these folks to learn more.

 We have seen some deployment issues in the field, and this may help improve your success rates.

 During disucssion during this ASM session, memebers of the audience did strongly recommend
 engaging Sun PS.

 Note that I have been called into several accounts where there were several issues. Some of these software
 packages are quite sophisticated, and have watch field teams cut Sun PS out of their budget and then
 send e-mails all over several aliases trying to find expertise, and then they get frustrated or in some unfortunate
 cases kinda guessing during the install and running into customer satisfaction issues.

Further reading:

See the ST 9900 Program Wiki,  and engineering white papers:

http://wikihome.sfbay.sun.com/Systems/Wiki.jsp?page=EngineeringInformation

In summary, ST 9900 virtualization is primarily for archival. We do strongly recommend characterization of the customer application and non-product Proof of Concepts. Engagement of Sun PS is also strongly recommended

Posted at 06:23PM Sep 18, 2008 by Kenneth Ow Wing in Personal  |  Comments[0]

ST 9900 Guidance: Substitution of disk drives. 145 GB 10 K and 300 GB 10K

What is the suggested substitutes for the 146 GB 10 K and 300 GB 10K HDD?

Before going to a solution, let's think about the customer is trying to accomplish.
A few years ago, when 300 GB and 146 GB capacities were big news, the customer
would buy for two main reasons: capacity and lowest $/GB. If a customer bought a 15K RPM HDD,
they were buying performance, and were wlling to pay a premium for that performance. If you think about
it, given the same capcacity, a 10K RPM HDD was less expensive than a 15K RPM HDD.

So with the above in mind, the customer who was interested in capacity, with the least $/GB, they would move from
146 GB 10 or 300 GB 10K to 400 GB 10K and in the future. They would be less inclined to move to a 146 GB 15K, 300 GB 15K or in the future a 450 GB 15K, since these higher performance HDDs come with a price premimum because of their performance advantages.

Posted at 06:20PM Sep 18, 2008 by Kenneth Ow Wing in Personal  |  Comments[0]