Viruses, trojan horses and spyware account for a large percentage of perceived performance bottlenecks. Users notoriously complain about the network, the application or their computer when nasties raise their ugly heads. Those performance killers can reside on one or more server systems, the user’s workstation, or a combination of the two. Malware infections are so common that you must employ multiple defenses against them. Antivirus, antispyware, local firewalls, network firewalls and a regular patching regimen will help protect systems and prevent resultant bottlenecks.
Smart workload management can help prevent performance problems associated with poorly balanced workloads or ill-conceived load balancing schemes. Adding another system to a suffering cluster relieves the pressure, but this is easier to do in a virtual environment than in a physical one. The best advice here is to measure capacity and performance of all systems and heed the numbers reported to you. Move workloads, add systems and keep a watchful eye on performance.
8. Failing or Outdated Hardware
The older the hardware, the more likely it is to fail. Some hardware components fail with a single final breath, while other linger on with random complaints and untraceable glitches. Hardware that causes system reboots, disappearance of data or performance bottlenecks frustrate system administrators because of its unpredictable nature. The best way to prevent such tragedies is to keep hardware fresh, use redundant hardware and monitor your systems carefully.
Did you know that your filesystem choice can have a profound impact on performance? It can. Some filesystems, JFS for example, uses very little CPU. XFS has very high scalability and high performance. NTFS is a recoverable file system with high performance. The new EXT4 filesystem supports very large files efficiently. Each filesystem has a purpose, and using the incorrect one for an application can have disastrous results. Consider your filesystem choices wisely and select the best one for the job. There is no one size fits all filesystem.
The technology you select for your infrastructure plays an important role in performance. For example, if you dedicate your services to a virtual infrastructure technology, you might have performance problems not experienced on equivalent physical systems. Alternatively, there are some workloads that thrive on virtual technology. LAMP (Linux, Apache, MySQL, PHP) workloads, for example, perform at and greater than native speeds on KVM. However, container-type virtualization (OpenVZ, Parallels, Solaris Zones) boasts native performance ratings for any workload.
Ken Hess is a freelance writer who writes on a variety of open source topics including Linux, databases, and virtualization. He is also the coauthor of Practical Virtualization Solutions, which was published in October 2009. You may reach him through his web site at http://www.kenhess.com.