We need your help to improve DB2 LUW. We just ran Episode #16 of The DB2Night Show™ with special guest Adam Storm, Software Developer, DB2 Kernel Development, IBM Toronto Lab. We talked about Autonomic Memory and STMM updates. Watch the Replay. The studio audience asked a few good questions, but a vigorous email discussion ensued after the show.
Long story short, STMM is either "ON" for a parameter or "OFF". It has a VERY LONG LEASH to grow and shrink memory pools. There are some people in the DB2 LUW community that have experienced performance degradation or problems with STMM (about 20 percent in our audience survey), and a number of professionals would be more interested in using STMM if it were possible to give STMM "a short leash" - that is, for each memory pool under STMM's control, be able to specify a minimum and maximum value range. By specifying a range, one could keep STMM from making a pool too small or excessively large.
Adam told us that ranges had been considered, but were dismissed in favor of ON/OFF (I guess that was easier to implement). He also told us that range limits for STMM could be implemented if there was enough interest within the DB2 LUW community in favor of range specification capability.
Here's where you can help. We've made it really easy. Just click this MAILTO:firstname.lastname@example.org?subject=I support STMM Min Max Value Ranges link, add some text to the body of your message (optional), then click your SEND button.
Read just a bit more...
This email address is an alias that forwards mails to real email addresses of people who care. Bots and Spammers will likely find it, and on 31 May 2010 the alias will be deleted and the sanctuary of the intended recipient email boxes will be restored.
If you missed it, we also talked about STMM during Episode #14 "Crunching the Numbers". During this show, we did a live demo of STMM in action on a DB2/AIX server and revealed some normally unspoken truths about STMM. Watch the Replay
UPDATEAfter writing this initial blog post, Adam contacted me and expressed a few concerns. It seems that "social media" may be an unfamiliar venue for IBM to collect enhancement requests, and he cautioned that there should be no implication that IBM is bound to create this enhancement if a 1,000 or 1,000,000 people vote in favor of it, that unrealistic expectations should not be set, and he worries that "it creates a public perception that there are back-channel methods to getting features integrated into our product which is also not necessarily true".
I have politely reminded him that not every DB2 LUW user gets invited to participate in IBM CAC (Customer Advisory Council) meetings, and that the DB2 LUW community needs a voice and a channel to convey product improvement suggestions. We are all interested in having the best DB2 product possible. Please SEND the email if you think this enhancement is a good idea, and feel free to embellish your thoughts in the body of your email.
Our Shameless Marketing MomentToo many organizations around the globe suffer from HARDWARE ADDICTION. Hardware upgrades are an extremely costly bandage, often ineffective, and frequently unnecessary. At one customer site, we reduced the number of pSeries CPUs required from 56 down to 28 in 45 minutes.
Database vendors claim that their databases are capable of self tuning, but watch episode #14 of The DB2Night Show and you will see the full truths revealed. If your "automatically tuned" database fails to meet performance expectations, your same vendor will be delighted to sell you upgraded hardware or On Demand CPUs.
Further validating that databases are not capable of achieving performance optimization at minimal cost on their own, the database vendors also sell extra cost performance analysis tools. One of DBI's customers reported to DBI that said database vendor's performance tool took over a month to install, required several calls to Germany, frequently crashed, and added some 20% overhead to their system. Ah yes --- well, that is to be expected --- these nice folks are in the hardware business and they license their database and tools according to the installed processor capacity.
Stop letting the fox watch your hen house
And BREAK FREE from Hardware Addiction