Flashtec NVRAM accelerator achieves 15 million iops at a latency of several microseconds

Flashtec NVRAM accelerator achieves 15 million iops at a latency of several microseconds

Enterprisetech

PMC has recently provided a brand new product for very large-scale data center operators and enterprise-level storage vendors to help them build more avant-garde storage infrastructure. PMC was founded thirty years ago. As an industry-recognized semiconductor company, it previously specializes in communication equipment and has entered the enterprise storage market in seven years. The company has just developed a non-volatile memory card based on the dram primary memory and flash memory, achieving an astonishing 10 million iops (input/output times per second ).

This winning speed is only 10 times faster than the PCIe Card Based on nand flash memory, so the outstanding performance is bound to attract the attention of many companies who intend to accelerate their applications.

The new NVRAM accelerator card is named flashtec. It is based on the Controller Developed by PMC to support the nvme protocol. The nvme protocol has been released in recent years. It aims to enable the CPU and main memory to focus on the flash devices in the Processing System by detaching the operating system kernel and driver, thus greatly improving the flash memory performance. PMC launched the first 6 GB/sec SAS/SATA and 8 GB/sec fiber rechannel controller in 2007, followed by adaptec and added 12 GB/sec SAS products in 2012.

In the same year, PMC added a new player to support nvme flash and NVRAM controllers in its product line, reducing the latency of I/O operations, i/O computing time is reduced by more than half (compared with conventional SAS ). These controller products can connect up to 8 TB of flash memory to achieve 875,000 iops for random reading of 4 kb files. The series has two configurations: one with 16 channels for PCI-Express X4 slots and the other with 8 channels for PCIe X8 slots. PMC also sells SAS host bus adapter cards and last year released SAS/sata raid Controller cards. According to Roger peene, senior director of the product marketing department of PMC, in 2008, seven years ago, PMC's SAS port market share on the server was basically zero, the share has exceeded 50%. However, even more disruptive news was at this week's flash summit, where PMC used the industry's first nvme flash controller to create the world's first nvme-enabled NVRAM accelerator card.

Peene told reporters that the flashtec NVRAM accelerator card is a PCI Express card, which is different from the nvdimm card. The nvdimm card is used to place the flash memory in the module, and then insert these modules into the main memory slot of the server in multiple ways. First, nvdimm requires BIOS support, consumes extra energy from memory slots, and competes with applications for processor cycles and memory bus bandwidth. Nvdimm is also closer to the processor. Since the memory bus is much faster than the PCIe bus, many people think that nvdimm is the preferred solution. However, the NVRAM hybrid solution released by PMC combines the strengths of flash memory and DRAM so that they can be used as both memory and ideal block storage devices.

The uniqueness of this product is here, because the flash TEC accelerator card is used in a variety of ways. When an application uses the nvme interface for block-based access, it uses storage terms such as opening, reading, and writing, and uses a fixed block size to access dram on the card, and access to flash or disk storage. In another faster memory ing access mode, the card has a direct memory interface with 64-Bit Memory ing and addressing, the application uses the memory term-load and storage, while the DMA engine accesses the data stored in dram on the card. In these two usage modes, the data stored in DRAM is always instantly backed up to the flash memory.

Peene said that if you want to use flashtec as the write cache, You need to configure it as a block device, but if you want to update metadata or database records, the more comfortable way is the memory ing mode. In any case, the card speed is amazing.

According to peene, in memory ing mode, for 4 kb random reads, flashtec can reach a peak iops of 4.3 million; for 4 kb random writes, its peak is 4.6 million. (DRAM can achieve almost the same read and write performance. However, flash memory alone cannot achieve this .) In terms of reading performance, the performance of the card is about 10 times that of the solid state disk. If the focus is on the Write Performance of metadata and database load, flashtec can achieve 15 million iops under 64-bit random write conditions, which is about 100 times the performance of SSD. (The iops that SSD can reach is about 50,000 to 100,000 ). In block mode, for 4 kb files, the flashtec NVRAM acceleration card can reach about 1 million iops.

The flashtec accelerator card can also be partitioned and run in both memory ing and block mode. It shows NVRAM's performance in latency and its corresponding location at the storage level:

Flashtecnvram accelerator Card series with 4 GB, 8 GB, 16 gb dram memory respectively. PMC mainly uses the micron technology product as the memory and flash chip on the card, and is seeking a second component supplier. PMC did not explicitly inform the card of the amount of flash memory, but pointed out that the size of the flash memory on the card is at least twice that of the dram capacity, so that users can make at least two backups of the data on the dram. Peene mentioned that the maximum capacity required for database and metadata caching is 16 GB, so 1 TB or 2 TB of DRAM and flash memory are not required on the card. (Although from the perspective of engineering design, the consideration of large capacity still has its own challenges, and there may be some suitable application scenarios ...) It takes less than 30 seconds to back up dram content to the flash memory. A total of more than 5,000 backup cycles can be processed. Restoring data from the flash memory to DRAM takes less than 60 seconds.

The NVRAM accelerator card of PMC was designed to solve the essential defects of DRAM primary memory and flash memory. DRAM is prone to loss. When the power supply fails, the data on it no longer exists. Flash memory is not easy to lose, which means that the data on it can be stored for several months without any power supply. However, flash memory units are lost with each write cycle. In addition, the flash memory consumes more time, and the block on the flash memory must be overwritten before writing new data to the flash memory, thus increasing the loss process. The daily write (DW/D) of the flash SSD is limited to 10 times, and according to peene, the daily writes required by the enterprise storage are 50 to 1,000 times. Flash Memory obviously cannot reach such an indicator. PMC believes that before other types of non-volatile storage are available, the NVRAM accelerator card is an ideal solution, that is, combining DRAM and flash memory to back up dram, when the server power supply goes wrong, the super capacitor module on the card backs up data from memory to flash memory. The existence of super capacitors allows server vendors or ultra-large data center operators to design and use devices without the need to add uninterrupted power supplies or battery backup units to the main memory for critical loads in the system, this greatly reduces the cost of the entire rack.

Any application involved in the Flash layer may benefit from the acceleration feature of the flashtec accelerator card. Possible applications include using it for metadata storage in a horizontally extended file system or as a high-speed cache layer in a full-flash array. Flash TEC can also be used to improve the performance of In-memory database logging, which is far better than SSD or flash-based PCI-Express card.

The flashtec NVRAM accelerator card can be inserted into the PCI-Express 3.0 X8 slot, with a half-Height size. The Redhat Enterprise Linux 6.5 and 7.0 are embedded with support for this card. Obviously, other operating systems will follow suit. PMC said that, compared with other NVRAM products on the market, flashtec accelerator card pricing will be very competitive. The flashtec accelerator card will be available in the fourth quarter. Currently, some customers who use this technology first are conducting samples.

Flashtec NVRAM accelerator achieves 15 million iops at a latency of several microseconds