This category contains 24 posts

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

Oracle Clusterware on RHEL5/OEL5 with udev and multipath

The trouble with Linux? No… the trouble with computers in general – is that they keep changing! Solaris 10 comes out, Oracle 11g, Red Hat 5… and everything works different!! It’s a full-time job just trying to keep up with everything. Almost exactly one year ago I wrote about using udev on 2.6 kernels to … Continue reading

Oracle I/O and Operating System Caching

Well it’s been awhile since I’ve written anything for the blog – during the past four months I went on a trip to Asia, celebrated Thanksgiving and Christmas with both my family and my girlfriend’s family and then in January I got engaged! I’ve also been working on some continuing educational goals – so needless … Continue reading

Monitoring Oracle on SMP with Hyper-Threading

So I’ve really been digging Kevin Closson’s blog lately. Back at the beginning of this month he had another post that caught my attention about running Oracle on Opteron in which he made the point that these boxes should always be run in NUMA mode (not SUMA). This grabbed my eye because I’ve been delving … Continue reading

Monitoring Oracle on NFS

Wow – the last three weeks have been crazy! During the last week of May I was wrapping up the services paper and a few submissions for the UKOUG. And for the first two weeks of June I’ve been working on some performance problems for one of our clients in the Phoenix area. Nice weather … Continue reading

Who’s Accessing That File?

From the occasionally-useful-scripts library… It’s like fuser but shows name of the process (args[0]). Needs lsof installed. I’ve used it on Linux and Solaris. nap01:~$ cat jduser #!/bin/sh [ -n “$1” ] && [ -d “$1” ] || { echo “Usage: $0 [dir]”; exit; } AWK=awk; [ “`uname`” = “SunOS” ] && AWK=nawk; lsof +d … Continue reading

The Clusterware C API

Well I’ve been incognito for the past two weeks or so because I’ve been finishing up a pretty detailed paper about Oracle Services. Finally finished up the first draft yesterday… it’s 16 pages in the IEEE Computer Society article LaTeX class – which doesn’t leave much whitespace! It’s a pretty comprehensive review of pretty much … Continue reading


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