Server-based SSD definition


A server-based SSD is a solid state drive that may be manufactured in a PCI Express form factor. It could also be a SATA or SAS drive that plugs into the standard SATA/SAS interface, allowing it to be installed directly into a server.

Server-based SSDs can function as a cache in the server or as persistent storage, allowing the SSD server to have essentially an extremely fast scratch disk for very frequently accessed data. Putting this high performance storage directly in the server reduces latency because the server doesn’t have to access data on an external storage array. Because of this, server-based SSDs are high performance direct-attached storage. These SSD server drives are typically NAND flash-based.

Server-based SSDs are most often used for frequently accessed data in a database. Some examples of this are database indexes or whole databases. These best-use cases can reduce data access latency by as much as 90%. Both server vendors as well as some storage vendors offer server-based SSDs.

SSD technology helps reduce server sprawl

Solid-state drives are still more expensive than spinning disks, but SSD technology can improve I/O performance, reducing the number of servers and storage arrays you need.
The more you spend, the more you save. That's what some IT managers find when, in their effort to improve I/O performance,... Last year the reference website Answers.com began to experience I/O performance bottlenecks on its database servers, which were Hewlett-Packard Co. BladeSystem ProLiant Server Blades. Answers.com runs the MySQL databased and configures each cluster with a master database server, plus a farm of read-only, synchronized database slaves that handle the bulk of queries.
As the site grew and received more updates, it became difficult for these slaves to serve incoming requests quickly -- and handle the replication updates coming from the master -- and response times were taking a hit.

Tackling I/O issues with SSD technology


Usually, the solution to I/O problems is to connect servers to storage arrays configured with lots and lots of spinning hard-disk drives, "but that's not very economical to house and maintain and to pay for in terms of power consumption," said Dan Marriott, the director of production operations at Answers.com.
Nor could the firm simply add more nodes to its clusters.
"We can't buy unlimited servers; we have realistic hardware budgets," Marriott said.
Instead, Answers.com tried to put SSD technology in the slave servers. The company moved the database copy from internal disk drives to a 320 GB HP StorageWorks IO Accelerator, a NAND flash-based storage adapter that HP OEMs from Fusion-io, and replication recovery time decreased from 6 hours to 12.5 minutes, Marriott said.
ROI from SSD technology. In addition, the flash drive boosted the number of complex queries the servers could perform from 350 per second to 3,500 per second, and it improved application response time by 30%. That in turn allowed Answers.com to reduce the number of servers in each database read cluster from 20 down to five, for a net cost savings.
Even though the IO Accelerator cards cost about twice as much as an individual server, "we got immediate [return on investment]," Marriott said. Using approximate numbers, given a typical database cluster with 20 $5,000 servers, the company equipped five servers with a $10,000 flash drive, for a cost of $50,000, and repurposed the remaining 15 servers for a savings of $75,000.
"Deploying these Fusion-io cards actually saved us $25,000 in Capex for each of our database clusters, right off the bat," Marriott said.
Beyond that, Answers.com enjoys improved operational savings from the reduced number of servers, including admin time, space in its racks, power and cooling, and fewer points of failure, Marriott said.
"Less hardware equals less failure," he said.
Installing the card and its driver is "trivial," Marriott said. "It's the simplest thing; you just add the mezzanine card, which takes about 60 seconds. Then you reboot the server, install the driver, format the drive, then you copy your data across, and away you go."

SSD technology en masse


Of course, using Flash to improve performance is nothing new, but the use of SSDs in the enterprise is on the rise, said Jeff Janukowicz, IDC's research manager for SSDs. It's still an early market, but IDC expects that between now and 2014, shipments of enterprise SSDs will grow by 75%, he said.
IDC attributes SSD's growth in the enterprise to two factors: decreasing cost and the rise of multicore processors. Over the past decade, the price of NAND memory decreased by 50% per year, Janukowicz said. On a dollar-per-gigabyte basis, SSDs still cost about 28 times that of traditional hard disk drives, but IDC expects that number to continue to drop.
"We don't anticipate that SSD will ever be cheaper than hard disk drives, but that's not really necessary," Janukowicz said. "It's more about leveraging SSDs for what they can bring to the system."
At the same time, faster microprocessors have an increased thirst for fast storage subsystems.
"Moore's Law and recent advancements in processor power have put pressure on storage subsystems to keep the processor filled with data," Janukowicz said.
Fusion-io's SSD-on-PCIe adapter card is but one variation on the enterprise SSD theme. SSD is often integrated into traditional storage arrays, such as EMC's FAST, as a high-speed storage tier. On the device side, STEC, Pliant Technologies and other companies create serial-attached SCSCI (or SAS) drives based on SSD, and traditional hard disk drive manufacturers such as Seagate have also gotten in on the act. Finally, Violin Memory Inc. and Texas Memory Systems Inc. are among the companies that offer entire storage arrays created from SSD.
The real challenge is identifying which applications can make effective use of SSD technology, Janukowicz said. Workloads that are good candidates for SSDs include databases, online transaction processing, streaming video on demand and even virtual desktop infrastructure.
"In general, any workload that is I/O-intensive, those are the ones that will benefit the most," Janukowicz said.
Write-intensive applications, meanwhile, may or may not benefit from SSDs, Marriott said. But generally speaking, "if you're seeing performance problems because of I/O limits, there's a pretty good chance that Fusion-io or other enterprise-grade SSDs can be a game changer."

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LỜI BÀI HÁT
Ver 1:

Ngay từ đâu tao nói là đây ko phải trận chiến
Mà là lớp học để tao dạy lại cho mấy thằng điên
Tụi mầy phiền tao ko cần biết, nhưng có tao tụi mầy cần biến
Vì tao đã thấy được mục đích của mầy từ đầu, mầy tìm đến đây là mầy cần tiếng
Đã mầy ngu từ sinh ra thì làm cái đéo gì biết lí lẽ
Nghe người ta ra bài dizz mình thì lấy tờ giấy mà làm thí mẹ
Tụi mầy đi khoe, xem nhạc của mầy vs nhạc của tao thì ai đứng nhất
Đối vs ai tao ko cần biết, nhưng đối với mầy nhạc tao đúng chất
Và đó chắc cũng là lý do, nhạc của mầy mãi ko đứng top
Mầy kéo tiểu đội mầy ra, tao đã nói mình tao chấp nốt
Bài mở đầu tao đã đề rõ CHÀ BÁ ra là chỉ một chữ GẸO
Vậy đừng hô lên với hàng xóm, nhạc tao hài khiếp nghe mấy chú dẹo
Muốn dizz người ta ra nhục, thì phải biết được địch biết ta
Tao chỉ viết, được có 1 ver mà tụi mầy chia nhau xé thiết tha
Thì cũng chứng tỏa nhạc tao dần dần ăn sâu vào máu rồi lên tới não
Bài dizz tao lượt like thì ít,mà nghe thì nhiều bởi thế mới ảo =))

Hook:

Tụi mầy ra hết đi mấy thằng chó, chổ tao cần ko phải con hoang
Xích cái mỏ nó lại tại đó, lập luôn bàn thờ cúng lại cầu an
Và nhạc tao đang, âm vang muốn nghe thì cứ từ từ nhấn play mà phiên
Mầy phải cảm ơn vì tao khơi sáng, đừng có làm phản nghe mấy thằng điên

Ver 2:

Còn thằng Wako là ai? Thằng Dr .Khoi là ai ?
Và thằng V.Soul, nó có liên quan gì tới tao mà nhai
Làm nhục ông Shyn, hay là ko thì chắc rằng ai cũng biết
Chỉ có thể loại ngu si như mầy, nội dung tầm bậy, cũng viết
Tao xin nhắc lại là 1 lần nữa, có ngon kéo đông kình tao
Ko lẽ một đóng, bài nhạc của tao chỉ để thể hiện trình sao ?
Và tao ko rảnh dành nhiều time để cho bon ngu thiểu năng
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Mà khi tao rap ở trong lần này, xuất thân là ko phe phái
Một mình tao chấp hết bọn mầy thì mầy đừng sợ teo dái
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Vì ngay từ đầu mầy gangz hổ báo rồi thấy tao hài lại hài theo là sao ?
Tao ko cần nói ko lẽ tụi mầy ko đủ biết
Tính sơ sơ là xong bài này tao thấy là lực cũng đủ giết
Nếu muốn rep thì mầy cảm thấy hay hơn bài này thì mầy chơi
CÒN NẾU KHÔNG THÌ VỀ RAP LOVE NHƯ MẤY THẰNG KIA ĐI MẦY ƠI

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