Ran into a situation on a customer’s CentOS server the other day where a service wasn’t working. Symptoms and error messages indicated the disk was full. However ‘$ df -h’ was showing ample free space. What the heck? Turned out … Continue reading
MySQL offers native support for connecting via SSL. By default this is available in AWS RDS MySQL instances. Using this connection method effectively encrypts all data going back and forth between the client and the server. This prevents eavesdropping (aka … Continue reading
Ran a very specific benchmark of MySQL – the native SSL connection performance penalty on AWS RDS. When establishing a MySQL connection there is a way to tell the server to use SSL to encrypt the communication between the client … Continue reading
When trying to build SysBench 0.4.12 you may be getting an error like: /bin/sh ../libtool –tag=CC –mode=link gcc -pthread -g -O2 -o sysbench sysbench.o sb_timer.o sb_options.o sb_logger.o db_driver.o tests/fileio/libsbfileio.a tests/threads/libsbthreads.a tests/memory/libsbmemory.a tests/cpu/libsbcpu.a tests/oltp/libsboltp.a tests/mutex/libsbmutex.a drivers/mysql/libsbmysql.a -L/usr/local/mysql/lib/ -lmysqlclient_r -lrt -lm ../libtool: line … Continue reading
Pngout is a free command line utility for compressing png files without any loss in image quality. Pngout compresses PNG files really really well (10-30% savings is typical). That translates into real dollars in terms of storage and bandwidth for large … Continue reading
I recently published a benchmark of EC2 vs RDS MySQL performance. This article is a follow up to that. Specifically, I’m comparing EC2 vs RDS in the situation where one EC2 instance is being used as a combined app server … Continue reading
MySQL benchmark of AWS RDS vs EC2 with complete results and instructions on how to recreate on your own for under $0.25. Update 9/15/2013 – Added bar charts to compliment tables. I found a couple blog posts with benchmark data … Continue reading
I came across an AWS Ubuntu 10.04 server running PHP 5.3.x that not was automatically clearing expired PHP session files. They were stacking up in /var/lib/php5/, to the tune of about 207k files and 834MB in just a few months. On … Continue reading
As of the current AWS API, setting the Expires and Cache Control headers for all objects in an AWS S3 bucket requires a script. It is possible to do it one file at a time through the AWS control panel, … Continue reading
Towards the end of every week, my version of WebLogic stops cooperating and shows a memory error when I try to start it. Error occurred during initialization of VM Could not reserve enough space for object heap Could not create … Continue reading
