Using the Network Speed Test Utility
Posted by Zoran Vasiljevic on 04 June 2007 8:46
As of 2.3.10, PresSTORE includes a simple, yet powerful network test utility. This utility can be used to check the data transfer speed between the PresSTORE server and any of it's clients (see Limitations below).|
The utility performs a pure network test, i.e. it does not read nor write any files, thus avoiding disk-speed to interfere with the measurement. It supports bidirectional data transfer: you can test both reading and writing of data from/to any registered client. Optionally, you can limit/extend the duration of the test, and, more importantly, configure/adjust network socket buffers to see which setup brings more speed.
The utility is exposed over the Command Line Interface (CLI) like:
cli::tests::net::readspeed client [-blocksize bytes] [-duration seconds]
cli::tests::net::writespeed client [-blocksize bytes] [-duration seconds]
The commands read/write data from/to the given client for a given -duration of seconds (default = 5 seconds) by setting the read/write socket buffers to -blocksize (default = system default). Both commands report speed in KBytes/sec.
The client must point to a configured and enabled client resource in PresSTORE server client database in order for the utility to work.
For details calling commands via the CLI please consult the CLI guide.
# cd /usr/local/aw
# bin/nsdchat -c cli::tests::net::readspeed imac
# bin/nsdchat -c cli::tests::net::writespeed imac
Here, all default values have been taken: the test were conducted for 5 seconds and both read and write socket buffers are left to the system-selected default. In some situations it is necessary to trim/adjust the socket buffers in order to get maximum possible network throughput.
# cd /usr/local/aw
# bin/nsdchat -c cli::tests::net::writespeed sparcsun
# bin/nsdchat -c cli::tests::net::writespeed sparcsun -blocksize 131072
As you see, by setting socket buffers to 128K, the speed between the current PresSTORE server and the given client (in this case a Sun Sparc system with Solaris 2.8 operating system) effectively doubles.
The utility does not support Mac OS X 10.3.9 or less. It also does not support speed tests between any Windows server and clients. When running on a Unix-like operating system, it does not support readtest from an Windows client. When running on a Windows operating system, it does not support writetest to any client.
The -duration argument should be extended to max 20 seconds, otherwise negative results may be reported (this is a known bug and will be fixed in one of the next releases).
The -blocksize argument shound not exeed 200KByte as some operating systems (most notably Mac OSX) will not support socket buffer sizes larger than that.