DFI - ddr-phy.org Overview at Maatkit Tutorial - Perf Wiki Linux kernel profiling with perf Introduction Perf is a profiler tool for Linux 2.6+ based systems that abstracts away CPU hardware differences in Linux performance measurements and presents a simple commandline interface. Commands The perf tool offers a rich set of commands to collect and analyze performance and trace data. The list of supported commands: Certain commands require special support in the kernel and may not be available. Events The perf tool supports a list of measurable events. Another source of events is the processor itself and its Performance Monitoring Unit (PMU). The perf_events interface also provides a small set of common hardware events monikers. Finally, there are also tracepoint events which are implemented by the kernel ftrace infrastructure. To obtain a list of supported events: An event can have sub-events (or unit masks). Hardware events PMU hardware events are CPU specific and documented by the CPU vendor. Counting with perf stat Modifiers multiple events
Rational Relational: Emulating The Missing RENAME DATABASE Command in MySQL I'll approach this topic from another direction. I had to perform a task which required moving tables between schemas on the same MySQL server. One way of doing this would be: Dumping the original table to disk.Creating new empty table on the target schema.Importing table from disk into the target schema. But, a simpler way exists! As long as two databases are on the same file system, you can use RENAME TABLE to move a table from one database to another:RENAME TABLE current_db.tbl_name TO other_db.tbl_name; Which works almost instantaneously and does what it is supposed to do. Using this command, it is easy to emulate the missing RENAME DATABASE command. Create the new schema.Perform a query to generate the move commands from the source to the target schema:SELECT CONCAT('RENAME TABLE ',table_schema,'.' Some notes: If you're using InnoDB foreign keys, worry not. The move command also moves the .idb files between the database directories, if you're using innodb_file_per_table. Hope this helps.
PacketShader - GPU-accelerated Software Router A GPU-accelerated Software Router New: The I/O engine is now available! We have partially released the source code used in this work. You can find the user-level packet I/O engine for Intel 82598/82599 NICs here. What is PacketShader? PacketShader is a high-performance PC-based software router platform that accelerates the core packet processing with Graphics Processing Units (GPUs). Why GPU? As you all know, GPU is a central chip in your graphics card. Packet I/O Optimization on Linux We implemented high-performance packet I/O engine for user-level application. Currently-available Linux network stack is not optimized for high-performance IP packet processing, say, for multi-10G networks. Huge packet buffer: Instead of allocating metadata (sk_buff or skb) and packet data for each packet reception, PacketShader pre-allocates two circular buffers that can hold a large array of metadata and packet data. Performance Figure 1 shows the performance of our optimized packet I/O engine. Figure 1.
10. Concurrencia 10.1 Introducción Como se mencionó anteriormente una de las grandes ventajas de emplear bases de datos y más especificamente de emplear un dbms es que se procure un buen manejo de la información, garantizando que todas las operaciones sean "ácidas", es decir, que cumplan con Atomicity: que las transacciones sean atómicas, se vean como una sola unidad Consistency: que los datos realmente estén bien relacionados y que no existan problemas de falta de información o falta de confiabilidad en los datos Isolation: aislamiento, separar las operaciones de distintas conexiones/usuarios unos de otros Durability: que se garantice la persistencia de los datos. Durante esta sección se tratan de abordar los conceptos de atomicity, consistency e isolation. 10.2 Transacciones 10.2.1 Definición Una transacción es una unidad de programa que accesa y posiblemente actualiza varios elementos de datos. 10.2.2 Estados de transacción 10.2.3 Programación Notas: 10.3 Control de concurrencia 10.3.1 Introducción Deadlock
Blade server IBM HS20 blade server. Two bays for 2.5" (6.4 cm) SCSI hard drives appear in the upper left area of the image. A blade server is a stripped down server computer with a modular design optimized to minimize the use of physical space and energy. In a standard server-rack configuration, one rack unit or 1U—19 inches (480 mm) wide and 1.75 inches (44 mm) tall—defines the minimum possible size of any equipment. Blade enclosure Enclosure (or chassis) performs many of the non-core computing services found in most computers. HP BladeSystem c7000 enclosure (populated with 16 blades), with two 3U UPS units below. Power Computers operate over a range of DC voltages, but utilities deliver power as AC, and at higher voltages than required within computers. The blade enclosure's power supply provides a single power source for all blades within the enclosure. Cooling Networking Storage Other blades Uses History Blade models See also References
MySQL Cluster Manager 1.1.2 – creating a Cluster is now trivial @ Andrew Morgan’s MySQL Cluster Database Blog MySQL Cluster Manager 1.1.2 is now available to download and try from Oracle E-Delivery (select “MySQL Database” as the product pack). Something that’s new and really cool in the new version is that you can download a version of MCM that actually includes the MySQL Cluster software itself and then you can have MCM automatically define, create and start a single-host cluster deployment for you with just the command “mcmd –bootstrap”. This post aims to show that it’s really as simple as that! I’ve been playing with Windows recently and so I’ll use that for this example but things would be very similar on other platforms. Step 1 Download from E-Delivery and extract the zip file Step2 Start your first cluster! PS D:AndrewDocumentsMySQLmcm> binmcmd --bootstrap MySQL Cluster Manager 1.1.2 started Connect to MySQL Cluster Manager by running "D:AndrewDocumentsMySQLmcmbinmcm" -a NOVA:1862 Configuring default cluster 'mycluster'... That’s it! So how much simpler is this than doing it by hand?
Announces eMMC 5.0 Total IP Solution at Mobile World Congress | Arasan Upcoming eMMC 5.0 specification will double performance of the eMMC interface. Barcelona, Spain– February 28, 2013 - Arasan Chip Systems, Inc. (“Arasan”), a leading provider of Total IP Solutions, announced today support for the upcoming eMMC 5.0 specification which is proceeding to ratification within the JEDEC standards organization. The eMMC Total IP Solution comprises digital and analog IP cores, software stack, firmware and a hardware validation platform. “Arasan has a track record of participating in standards development and delivering IP at the earliest possible time to satisfy customer needs,” said Andrew Haines, Vice President of Marketing for Arasan. Availability Arasan’s is currently engaging with early adopters for licensing of analog and digital IP cores, Verilog HDL for verification, software stack and firmware and sales of the hardware validation platform. About Arasan About eMMC
Live MySQL Conference, London, Oct 24th and 25th, 2011 Featured Speakers Peter ZaitsevPercona,CEO/FounderBaron SchwartzPercona,Chief Performance ArchitectDomas MituzasFacebook,Database EngineerAndrew AksyonoffSphinx,CEO/FounderYoshinori MatsunobuDeNA,Principal Infrastructure ArchitectMatthew A YonkovitPercona,Prinicipal Architect more speakers... Discover the Power of MySQL » Percona Live is an intensive two-days MySQL summit. There are many tracks of expert speakers, including Percona consultants and hand-picked guests. The sessions are 100% technical—even the sponsored sessions. Learn what works from leading companies who use MySQL.Hear how to drive down costs and improve performance with innovative solutions.Discuss your unique challenges and discover options for solving them.Meet face-to-face in the "hallway track" and make lasting connections.Engage the best and brightest in a lively job market. At Percona Live, you'll benefit from the expertise of the most accomplished system architects and developers in the business. Speaker List