The Cray MTA, formerly known as the Tera MTA, is a supercomputer architecture based on thousands of independent threads, fine-grain communication and synchronization between threads, and latency tolerance for irregular computations.
Each MTA processor (CPU) has a high-performance ALU with many independent register sets, each running an independent thread. For example, the Cray MTA-2 uses 128 register sets and thus 128 threads per CPU/ALU. All MTAs to date use a barrel processor arrangement, with a thread switch on every cycle, with blocked (stalled) threads skipped to avoid wasting ALU cycles. When a thread performs a memory read, execution blocks until data returns; meanwhile, other threads continue executing. With enough threads (concurrency), there are nearly always runnable threads to "cover" for blocked threads, and the ALUs stay busy. The memory system uses full/empty bits to ensure correct ordering. For example, an array A is initially written with "empty" bits, and any thread reading a value from A blocks until another thread writes a value. This ensures correct ordering, but allows fine-grained interleaving and provides a simple programming model. The memory system is also "randomized", with adjacent physical addresses going to different memory banks. Thus, when two threads access memory simultaneously, they rarely conflict unless they are accessing the same location.
A goal of the MTA is that porting codes from other machines is straightforward, but gives good performance. A parallelizing FORTRAN compiler can produce high performance for some codes with little manual intervention. Where manual porting is required, the simple and fine-grained synchronization model often allows programmers to write code the "obvious" way yet achieve good performance. A further goal is that programs for the MTA will be scalable – that is, when run on an MTA with twice as many CPUs, the same program will have nearly twice the performance. Both of these are challenges for many other high-performance computer systems.
An uncommon feature of the MTA is several workloads can be interleaved with good performance. Typically, supercomputers are dedicated to a task at a time. The MTA allows idle threads to be allocated to other tasks with very little effect on the main calculations.
The CrayMTA, formerly known as the Tera MTA, is a supercomputer architecture based on thousands of independent threads, fine-grain communication and synchronization...
2000, Cray was sold to Tera Computer Company, which was renamed Cray Inc. After the Tera merger, the Tera MTA system was relaunched as the CrayMTA-2. This...
technological facies of the Mousterian CrayMTA-2, a supercomputer based on the design of the never-built Tera MTA Message transfer agent or mail transfer...
in 2005, it supersedes the earlier unsuccessful CrayMTA-2. It uses the Threadstorm3 CPUs inside Cray XT3 blades. Designed to make use of commodity parts...
parallel random-access machine Cray XMT - a multithreaded supercomputing architecture, the successor to the CrayMTA-2 8-hydroxyfuranocoumarin 8-O-methyltransferase...
"Multi-processor Performance on the Tera MTA". 1999. Archived from the original on 2012-02-22. "Supercomputer maker to buy Cray, change name". cnet news. 2000....
code-name Horizon. Multithreading (computer architecture) Hyper-threading CrayMTA Tera Computer Company VLIW "The History of Computing at BRL". Padua, David...
The San Francisco Municipal Transportation Agency (SFMTA or San Francisco MTA) is an agency created by consolidation of the San Francisco Municipal Railway...
archived copy as title (link) "Cray History". Archived from the original on 2014-07-12. Retrieved 2014-08-19. "Cray's YarcData division launches new big...
through the paint. By mid-1986, the Metropolitan Transportation Authority (MTA) and the NYCTA were winning their "war on graffiti", with the last graffitied...
client computing, and virtualized computing. Notable Sun acquisitions include Cray Business Systems Division, Storagetek, and Innotek GmbH, creators of VirtualBox...
Ketchum, pp. 208–209 Ketchum, p. 211 Ketchum, p. 213 Scheer, p. 64 Cray, 2001 Cray, Robert E. (2001). "Bunker Hill Refought: Memory Wars and Partisan...
by the Maryland Transit Administration (abbreviated "MTA Maryland") and Charm City Circulator. MTA Maryland operates a comprehensive bus network, including...
Metropolitan Transportation Authority (MTA) began to repair yard fences and remove graffiti consistently. With the MTA consistently abating graffiti, many...
infected after undergoing the ritual. De Blasio put his wife, Chirlane McCray, in charge of major policy initiatives such as the Mayor's Fund to Advance...
in December 2019 by Rowman & Littlefield, Lanham, MD. In 2019, Chirlane McCray announced that New York City would build a statue honoring Graham near Grand...
Work 1923, p. 6 Birdseye 1879, p. 284 qtd. Root, Sawyer & Work 1892, p. 6 McCray 1898, p. 10 Tribble 1967, p. 423 McWhirter 2012, p. 146 Work 1923, p. 6 Root...
Retrieved 2021-08-05. "MTA Backs Off Plan For Major Bus Cuts". www.bizjournals.com. Retrieved 2021-08-16. Campbell, Colin. "MTA cancels proposal to slash...
Local officials Fernando Ferrer, vice chairman of the MTA (2011–present), former chairman of the MTA (2013, 2017, 2018–2019), former Borough President of...
former New York state senator and Brooklyn borough president Chirlane McCray, writer and activist, married to Bill de Blasio Max Rose (born 1986), U.S...
through the Stevensville Historic District, which contains the historic Cray House, the Stevensville Bank building, and Christ Church. MD 18A curves to...
Can't Dance" by Lou Reed "Sally's Got a Friend in New York City" by Larry McCray "Salmon Fishing In New York" by Orange Juice "A Salute to Harlem" by Boots...