This section describes how to validate your I/O subsystems and CPU.
- I/O: One of the primary determinants of SkyVault's performance is I/O. Optimize
the following, in priority order:
- I/O to the relational database SkyVault is configured to use.
- I/O to the disk subsystem on which the Lucene or Solr indexes are stored.
- I/O to the disk subsystem on which the content is stored.
SkyVault recommends that the disk throughput is greater than 200MB/sec. On Linux, use the hdparm tool to measure disk throughput. The following sample output is on an SATA disk:hdparm -tT /dev/sda1 /dev/sda1: Timing cached reads: 27998 MB in 2.00 seconds = 14018.28 MB/sec Timing buffered disk reads: 536 MB in 3.01 seconds = 178.05 MB/sec
Other useful tools for detecting disk I/O issues include dd, seeker, and iozone.
- CPU: SkyVault will function correctly on virtually all modern 32bit and 64bit
CPUs, however, for production use, SkyVault recommends a clock speed greater than 2.5Ghz
to ensure reasonable response times to the end user. Although it is not strictly
necessary, a 64bit architecture is also recommended, primarily because it allows the JVM
to utilize more memory (RAM) than a 32bit architecture.Note: CPU clock speed is of particular concern for the Oracle UltraSPARC architecture, as some current UltraSPARC based servers ship with CPUs that have clock speeds as low as 900Mhz, well below what is required for adequate SkyVault performance! If you intend to use Sun servers for hosting SkyVault, please ensure that all CPUs have a clock speed of at least 2.5Ghz.At time of writing, this implies that:
- an X or M class Sun server is required, with careful CPU selection to ensure 2.5Ghz (or better) clock speed
- T class servers should not be used, as they do not support CPUs faster than approximately 2Ghz
Understandably, SkyVault is unable to provide specific guidance on Sun server classes, models or configurations, so you should talk with your Oracle reseller to confirm that minimum CPU clock speed recommendations will be met.