Reducing Contention: Changing Default Isolation Level for Websphere Commerce (WCS)

Krafick

The Problem

I often lean on analogies when I speak to non-technical people about technical topics. For example, I would explain database locking as “two kids fighting for the same candy bar”.  If you introduce isolation levels into the conversation, I would expand the analogy to include “one sibling holding on to a candy bar they care nothing about just because they don’t want the other sibling getting to it”.… Read the rest

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Improving Performance of DBCLEAN Deletes

While this post is specific to WebSphere Commerce, it covers concepts that may apply to tuning other delete statements as well.

Using Functions in the Best Place

The CLEANCONF table stores the delete statements that are used by DBCLEAN. Most of them use syntax like this for the date component:

(days(CURRENT TIMESTAMP) - days(prevlastsession)) = ?
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Redesigning Tablespaces in an Existing Database

Like many applications, WebSphere Commerce puts all tables in USERSPACE1 unless they need larger page sizes. This actually works just fine for smaller and midrange implementations, but we have about one build a year that requires something else – either because of standards that client DBAs adhere to or because they actually are busy enough for I/O and separate buffer pools to matter.… Read the rest

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Updated: The 10 WebSphere Commerce Tables You Should Be Familiar With

One of my most popular posts that’s specific to WebSphere Commerce is The 10 Commerce Tables You Should Be Familiar With. This is an updated version of that post, since the preferred method of dealing with attributes has changed. As a result, this post is only applicable to WebSphere Commerce 7 and above, and some of the content is identical between the two posts.… Read the rest

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WebSphere Commerce Instance Creation Doesn’t Like DB2 9.7 FixPack 5

This post is specific to WebSphere Commerce. We spent a fair amount of time on this, both on a SUSE server and a Red Hat Server. The problem manifested in different ways. The main thing that became obvious to me is that Commerce was not creating the Commerce database as the dbaUser specified in createInstance.properties file, but was instead using the id that was running the Commerce Instance creation.… Read the rest

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