Oakies Blog Aggregator

TPC-Hベンチマークの続き
現在のディスク転送量は420MB/s強。

１セッションでこれ以上望めないのであれば、効率的な読み込み量を追求する。

オブジェクトを特定する

上の時系列スパイクチャートから、レスポンス要因はUser I/O

下のオブジェクトごとのDBアクティビティから、
LINEITEMのdirect path readが全体の78%の負荷が分かる。

だから、LINEITEMのREAD量を減らす、パーティショニング、コンプレス機能が効果的なことが分かる。

念のためにスパイクが飛び出た時のNo1 SQLのPlanを見てみると：
なるほど、LINEITEMへのアクセス負荷がポイントだな。。。

最後に、
Embarcadero® DB Optimizer™ XE を初めて使ってみたのだけど、
ものすごく簡単でした。

I’m in the later stages of implementing Oracle Enterprise Manager 11g for a customer. Right now there are rather too many metric collection errors for either myself or the customer to be truly happy with. There is remarkably little other than this post by Oracle’s Werner.de.Guyter on how to deal with these. Unfortunately whilst Werner’s [...]

With the recent news that the latest version of VirtualBox now supports shared disks, I thought I better give it a go and see if I could do a RAC installation on it. The good news is it worked as expected. You can see a quick run through here:

• Oracle Database 11g Release 2 RAC On Linux Using VirtualBox

This is pretty good news as that was the last feature that tied me to VMware Server. I’ve now moved pretty much everything I do at home on to VirtualBox and it’s working fine.

It’s worth taking a little time looking at the VBoxManage command line. Some of the operations, like creating the shared disks, have to be done from the command line at the moment. It’s also handy for running VMs in headless mode if you don’t want the GUI screen visible all the time.

Cheers

Tim…

There seems to be little debate that Oracle’s launch of the Oracle Exadata Storage Server and the Sun Oracle Database Machine has created buzz in the database marketplace. Apparently there is so much buzz and excitement around these products that two competing vendors, Teradata and Netezza, have both authored publications that contain a significant amount of discussion about the Oracle Database with Real Application Clusters (RAC) and Oracle Exadata. Both of these vendor papers are well structured but make no mistake, these are marketing publications written with the intent to be critical of Exadata and discuss how their product is potentially better. Hence, both of these papers are obviously biased to support their purpose. My intent with this blog post is simply to discuss some of the claims, analyze them for factual accuracy, and briefly comment on them. After all, Netezza clearly states in their publication: The information shared in this paper is made available in the spirit of openness. Any inaccuracies result from our mistakes, not an intent to mislead. In the interest of full disclosure, my employer is Oracle Corporation, however, this is a personal blog and what I write here are my own ideas and words (see [...]