Posted by VIP Experts on September 10, 2019
Servers are the core of today’s computational world, processing and storing data on multi-user platforms. Server performance depends on latency and capacity of its memory and storage. In general, DDR-DIMMs (Double Data Rate Dual In-line Memory Modules) are used as server memory, whereas SSDs/HDDs are used as storage in server. Whenever a service request is made to the server, it may require both data processing and storage. In order to execute this service, the processor accesses DDR-DIMMs and SSDs/HDDs. In addition, SSDs/HDDs can be accessed in case of power loss, storing data using backup power sources so data can be retrieved once power is available again.
SSDs/HDDs provide much slower access to the server in comparison to DDR-DIMMs, and it creates a performance gap. To overcome this performance gap between SSDs/HDDs and DDR-DIMMs, a new technology is evolving in the market referred to as NVDIMM. This new technology can provide performance somewhat near to DDR-DIMMs at SSDs/HDDs capacity.
Let’s review NVDIMM and its different types…
(To explain the analogy in the next few sections, RAM/DRAM can be read as DDR-DIMMs and Flash as SSDs.)
NVDIMM (Non-volatile Dual In-line Memory Module) belongs to the non-volatile RAM (Random-Access Memory) family. It works like RAM when power is available, and in case of power loss data is retained using an on-board backup power source and non-volatile storage. NVDIMM is a combination of storage and memory. At the front end of NVDIMM, it uses RAM which is volatile in nature, whereas at the back end it can use any NAND Flash storage which can be non-volatile in nature. Since NVDIMM contains volatile as well as non-volatile memory, it is expected to have a higher cost in comparison to DRAM.
The following figure shows where NVDIMM stands in terms of speed, size and latency when compared with other computer memory and storage.
There are mainly four types of NVDIMM in the market. Three of them are JEDEC standardized and one is not.
The JEDEC standardized NVDIMMs are:
The non-JEDEC standardized NVDIMM is:
The type of NVDIMM can be chosen based on features and requirements. Different types of NVDIMMs are compared below for reference:
NVDIMM memory technology can bridge the performance gap between memory and storage solutions with servers. NVDIMMs are applied in cloud computing and the data center market where power failure is critical and high performance is required. A short-term power failure, system crash or service interruption at servers can create a huge loss, so NVDIMMs can be used to prevent data loss and it provide faster access to non-volatile storage. All that said, the cost factor will determine how much market space is being captured by NVDIMMs.
In addition, Synopsys has announced the industry’s first LPDDR5 IP & VIP solution extending leadership in DDR5/LPDDR5 and strengthening our leadership in memory VIP. Synopsys also recently announced the industry’s first DDR5 NVDIMM-P Verification IP, showcasing continued collaboration with leading memory vendors. Synopsys is engaged with the early adopters of LPDDR5, DDR5, DDR4/5 NVDIMM-P and DFI 5.0 VIPs. For more information, please visit http://synopsys.com/vip.
In the next blog on NVDIMM, we will deep dive into NVDIMM-P technology.
Also, stay tuned for upcoming blogs on next generation DRAM and Flash memory technologies. Meanwhile, read our recent blogs on next generation memory technologies:
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