This category contains 71 posts

ASM Negative Free Space

In the last post I showed mathematically how ASM calculates the free usable space that it displays. However one of the first questions I received after presenting that internally was from someone concerned about all of the unusable space being saved just in case we lose a disk. (In my worked example it was 1/6 … Continue reading

ASM Space Calculations and Hot Spares

This is quick and dirty. I hope to get a more polished write-up of what it means and how it works, but since I’m so busy right now I don’t know if I’ll get to it soon. In the meantime someone just might find this useful or informative so I’m just going to put it … Continue reading

Future of OCFS2

At the company where I’m working right now, I’m part of an architecture effort to come up with our standard design for RAC on Linux across the firm. There will be dozens or possibly hundreds of deployments globally using the design we settle on. We’re internally debating whether or not we should include OCFS2 in … Continue reading

Oracle ASM Stripe Size

Right now I’m working on some internal documentation and referencing Oracle 11g’s Storage Administrators Guide (ASM manual). And I think there’s a bit of a contradiction here about the stripe size. ASM uses a variable “data extent” size when allocating space for files (like any sane filesystem) – the first 20000 data extents are equal … Continue reading

Parsing LISTENER.ORA with awk and sed

Happy Thanksgiving to everyone in the US! And happy belated thanksgiving to everyone in Canada since you celebrated back at the beginning of October. :) I’ve been doing a lot of scripting work lately. Although I can’t write about everything I’m doing, I would like to post a pattern that I thought could be useful … Continue reading

Oracle Fully Automated Install and Patch

Before I started consulting, I was an Oracle engineer in a very large software development organization. The company had a number of major products and the one I worked with was used by hospitals and radiology offices world-wide. (These guys are one of the biggest companies worldwide in the field.) Our product included the hardware … Continue reading

ASMLIB Performance vs Udev

Is asmlib obsolete on a modern Linux system? I’m still undecided but starting to lean toward “yes”. Everybody knows that asmlib was very useful when it was first introduced with Oracle 10.1 to simplify a host of issues on Linux: direct async device access without raw devices, file permissions & ownership without custom code, and … Continue reading

Collaborate Wrapup, RAC 11g/VMware Lab

So Collaborate is over and I’m back in Chicago… home sweet home. I thoroughly enjoyed the week in Denver, in spite of the snow! Thursday, the last day, was especially fun. First was a panel debate “To RAC or Not To RAC: What’s Best for HA.” Dan Norris invited me to participate in this panel … Continue reading

Oracle Services on RAC at Collaborate

Just a quick post to say that I’ve uploaded the slides from my services presentation at Collaborate and you can find them over on the publications page. Thanks to everyone who attended!! Great questions and comments throughout the session. Next time I’ll try to get through everything faster so that there’s more time for Q&A! … Continue reading

Oracle IOPS and HBA Queue Depth

About a month ago I wrote an overview of Linux Caching and I/O Queues as they pertain to Oracle. I was working on a project to architect, install and configure the beginnings of an 8-node cluster consisting of either one or two RAC databases. During the project, while I was waiting for the OS guys … Continue reading


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contact: 312-725-9249 or schneider @ ardentperf.com