When it comes to processing financial transactions, money can be won or lost in milliseconds. That's why high throughput, low latency, and consistent latency for transactions are the name of the game. Financial institutions are fanatical about their market data and trading systems, and Linux distros want to cash in on that.
The two key commercial Linux distributors, Red Hat and Novell, have both announced real-time variants of their respective distros: Red Hat Enterprise MRG (pronounced "merge" and short for messaging, real-time, and grid) and SUSE Linux Enterprise Real Time (or SLERT for short). Novell got into the real-time game first of these two companies, with the first SLERT 10 release launched in September 2006 with partner and long-time real-time operating system provider Concurrent Computer.
The third release of SLERT 10, which came out in November 2007, was gutted and a real-time patch set called CONFIG_PREEMPT_RT replaced the code Novell and Concurrent originally cooked up, and Red Hat's Enterprise MRG variant of RHEL is also based on this same patch set. (Concurrent, Red Hat, Novell, IBM, Silicon Graphics, and a few others have contributed to the real-time kernel patches, and Red Hatter Ingo Molnar manages this open source project).
Red Hat threw its hat into the real-time ring in December 2007 and started rolling out the real-time and messaging parts of the RHEL variant in June of this year. Both SLERT and Enterprise MRG only run on 32-bit x86 or 64-bit x64 processors architectures. Their regular Linuxes also run on IBM mainframes and Power servers as well as various Itanium-based servers.
Both Novell and Red Hat want to prove that these real-time variants of their respective Linuxes provide low latency at high throughput and therefore justify the extra licensing fees that both companies charge for the products. And to that end, both companies have asked the Securities Technology Analysis Center, which runs a financial application benchmarking center in New York and which also sells a bunch of tools to help financial institutions measure and tune the performance of their own applications, to put these Linuxes through the paces and demonstrate the performance benefits compared to normal Linux distros.
And to make comparisons easier, both Novell and Red Hat asked STAC to test the real-time Linuxes running the Reuters Market Data System at the 6.3 release level. This Reuters application gathers up financial information from myriad sources and then distributes it out to traders, brokers, and other financial end users who are relying on this information to give them an edge. Reuters also provides a benchmarking suite for prospective customers, and this is what STAC used in the tests.
The specific test was for what Reuters calls point-to-point server (P2PS), which is what you do when you want to stream a high volume of market data to dedicated desktops on your network.
Red Hat put out its performance numbers first, setting up Enterprise MRG 1 on six of IBM's HS21 two-socket blade servers. Each blade was equipped with two quad-core Xeon E5440 processors, which run at 3 GHz, and 16 GB of main memory. The blades had two Gigabit Ethernet ports and two T320 10 Gigabit Ethernet dual-port adapters from Chelsio Communications. The IBM BladeCenter chassis used in the test had a 10 Gigabit switch from Blade Network Technologies in the box. Red Hat did two runs, changing the size of messages streamed to the desktops (what is called the maximum transmission unit), running the test at 1500 bytes and then 9000 bytes.