I'd rather play golf

SQL Anywhere has offered support for clustered indexes since the 8.0.2 release. There is no physical difference between clustered and non-clustered indexes in SQL Anywhere; any index can be marked as clustered, including those indexes implicitly created for the maintenance of referential integrity constraints. Moreover, one can apply or remove the “clustering” attribute of an [...]

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Tracking down table- or row-level contention amongst concurrent SQL Anywhere connections can be difficult to debug. In this tutorial, I’ll illustrate how one can use Application Profiling in Sybase Central to capture blocking events, which can help pinpoint where the contention is occurring and why. As my example, I’ll utilize two DBISQL connections connected to [...]

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In SQL Anywhere Version 10 we introduced Application Profiling, a set of graphical tools that could not only assist DBAs to diagnose performance problems but could also recommend solutions to common performance problems discovered during the analysis. Included in Application Profiling is a (cheap) mechanism to capture queries (and their access plans) that consume a [...]

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Despite our efforts at making relational database systems such as SQL Anywhere self-managing, self-tuning, and self-healing, there remains the need to be able to diagnose and repair performance problems. In part, this requirement is due to the overall complexity of the optimization task. Query optimization is – still – an NP-hard problem and the input [...]

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This past Friday afternoon (22 May 2009) I listened to Ahmed A. Soror present work on a Virtualization Design Advisor for DBMS Workloads, follow-on work to a preliminary paper presented last summer at SIGMOD 2008 (Vancouver). Ahmed’s co-authors include a fellow graduate student, Umar Farooq Minhas, faculty members Ken Salem and Ashraf Aboulnaga, all from [...]

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In our whitepaper on capacity planning with SQL Anywhere, Ivan Bowman and I stress the importance and difficulty in properly scaling a production database to create a representative test instance: Because constructing synthetic databases can take a significant degree of effort, often a representative production system is used as the test workload database. While such [...]

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Today and tomorrow I’m attending the 2008 CASCON conference in Toronto, co-sponsored by the Center for Advanced Studies at the IBM Toronto Laboratory and Canada’s National Research Council. Part of the conference includes the Fifth International Workshop on Engineering Autonomic Software Systems, which was my primary reason for going. I found one paper presented in [...]

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Recently one of my staff, Dan Farrar, put together a comprehensive whitepaper describing how to diagnose application performance with the Application Profiling toolkit found in SQL Anywhere versions 10 and 11. The final draft has yet to be placed on sybase.com, but I’ve put the draft on this site – you can find it here. [...]

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Recently I’ve received some questions/criticism about software (DBMS) self-management as a goal, not specifically regarding SQL Anywhere but in more general terms. The argument is that while self-management is a worthwhile vision, it’s a utopia that is unachievable. What’s implied is that because this utopian vision can’t be implemented, any efforts toward self-management aren’t worthwhile. [...]

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There is perhaps no other scientific field like Computer Science that can re-invent technology on such a regular basis and call it “new”. This is certainly true with the latest virtualization systems now available, such as VMware and Xen; twenty-five years ago I was a performance specialist with VM/CMS on IBM mainframes. The goals of [...]

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