Speeding up Oracle disk I/O on RHEL4 systems
While poking around the web last wek, I came across a good paper from Redhat that describes how to utilize asynchronous and direct I/O with Oracle. I have been using the Oracle...
View ArticleMonitoring Linux server performance with procallator
I manage a fair number of Linux hosts, and like to keep tabs on how my systems are performing. One way I accomplish this is with procallator, which is a Perl script that collects performance data that...
View ArticleTuning network and vm settings on CentOS Linux servers with ktune
While poking around the CentOS package repository, I came across the ktune package. Ktune comes with a set of kernel tunables that are useful for network and disk intensive workloads, and provides the...
View ArticleWhy isn’t Oracle using huge pages on my Redhat Linux server?
I am currently working on upgrading a number of Oracle RAC nodes from RHEL4 to RHEL5. After I upgraded the first node in the cluster, my DBA contacted me because the RHEL5 node was extremely sluggish....
View ArticleGetting an accurate view of process memory usage on Linux hosts
Having debugged a number of memory-related issues on Linux, one thing I’ve always wanted was a tool to display proportional memory usage. Specifically, I wanted to be able to see how much memory was...
View ArticleNotes from episode 28 of TGIK: Exploring CockroachDB on Kubernetes
Over the past few months I’ve been trying to learn everything there is to know about Kubernetes. Kubernetes is an amazing technology for deploying and scaling containers though it comes with a cost....
View ArticleNotes from episode 12 of TGIK: Exploring serverless with Kubeless
Over the past few months I’ve been trying to learn everything there is to know about Kubernetes. Kubernetes is an amazing technology for deploying and scaling containers though it comes with a cost....
View ArticleNotes from episode 13 of TGIK: Serverless with Fission
Over the past few months I’ve been trying to learn everything there is to know about Kubernetes. Kubernetes is an amazing technology for deploying and scaling containers though it comes with a cost....
View ArticleNotes from episode 14 of TGIK: Serverless with OpenFaaS
Over the past few months I’ve been trying to learn everything there is to know about Kubernetes. Kubernetes is an amazing technology for deploying and scaling containers though it comes with a cost....
View Articleatexit() stage right. Or how my Python program leaked file descriptors.
A year and a half ago I started using prometheus and grafana to graph metric data. This combination is incredibly powerful and I have been absolutely blown away by the amount of actionable intelligence...
View ArticleTiming out and killing Linux commands if they don't complete in a certain...
This past weekend I was working on a software project and needed to kill a job if it didn’t complete in a certain amount of time. The coreutils package ships with the timeout utility which is ideal for...
View ArticleCreating multi-node Kubernetes test clusters with KIND (Kubernetes In Docker)
The Kubernetes ecosystem is rapidly evolving, which means tools, frameworks and ways to approach running Kubernetes in production are constantly changing. To keep up with these changes I used to use a...
View ArticleUnderstanding the network plumbing that makes Kubernetes pods and services work
This morning I wanted to better understand how requests to ClusterIPs get routed to Kubernetes pods. Properly functioning networking is critical to Kubernetes and having a solid understanding of what...
View ArticleThe beginners guide to creating Kubernetes manifests
As a long time Kubernetes user the question I hear most often is “how do I create manifests (the file that describes how to create and manage resources in a cluster)?” When I ask the person posing the...
View ArticleNotes from episode 79 of TGIK: YTT and Kapp
Over the past few months I’ve been trying to learn everything there is to know about Kubernetes. Kubernetes is an amazing technology for deploying and scaling containers though it comes with a cost....
View ArticleNotes from episode 45 of TGIK: Calico
Over the past few months I’ve been trying to learn everything there is to know about Kubernetes. Kubernetes is an amazing technology for deploying and scaling containers though it comes with a cost....
View ArticleCreating a set of random numbers from the command line
This past weekend I was doing some database testing and needed to generate some random numbers to populate a table. My typical go-to utility for generating one random number is head piped to od and tr:...
View ArticleSeeing what changed in a docker containers file system
Docker has a number of nifty options to help investigate containers and container images. One option I have used over and over to debug issues is the docker “diff” command. This dumps out the files...
View ArticleHow the docker container creation process works (from docker run to runc)
Over the past few months I’ve been investing a good bit of personal time studying how Linux containers work. Specifically, what does docker run actually do. In this post I’m going to walk through what...
View ArticleConverting X509 certificates to JSON objects
Years ago when I wrote ssl-cert-check I looked far and wide for an easy way to parse X509 certificates. I wasn’t able to find a utility so I ended up using a combination of sed and awk to extract...
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