Cisco Data Center SSDs
As SSD technology evolves, manufacturers are improving their reliability processes. With maturity, reliability will become a smaller differentiating factor in the choice between SSDs and HDDs. With the availability of latest SSDs at higher capacities, combined with better performance and lower cost, they are increasingly becoming an obvious storage choice for enterprises.
To meet the requirements of different application environments, Cisco offers both enterprise performance SSDs and enterprise value SSDs. They all deliver superior performance compared to HDDs; however, enterprise performance SSDs support higher read-write workloads and have a longer expected service life. Enterprise value SSDs provide relatively large storage capacities at lower cost, but they do not have the endurance of the enterprise performance SSDs.
Cisco uses several different technologies and design requirements to help ensure that our SSDs can meet the reliability and endurance demands of server storage.
Reliability depends on many factors, including use, physical environment, application I/O demands, vendor, and mean time before failure (MTBF).
In challenging environments, the physical reliability of SSDs is clearly better than that of HDDs given SSDs’ lack of mechanical parts. SSDs can survive cold and heat, drops, and extreme gravitational forces (G-forces). However, these extreme conditions are not a factor in typical data centers. Although SSDs have no moving heads or spindles, they have their own unique stress points and failures in components such as transistors and capacitors. As an SSD ages, its performance slows. The SSD controller must read, modify, erase, and write increasing amounts of data. Eventually, memory cells wear out.
Some common SSD points of failure include:
>>Bit errors: Random data bits may be stored in cells.
>>Flying or shorn write operations: Correct write content may be written in the wrong location, or write operations may be truncated due to power loss.
>>Unserializability: Write operations may be recorded in the wrong order.
>>Firmware: Firmware may fail, become corrupted, or upgrade improperly.
>>Electronic failures: Even though SSDs have no moving parts, physical components such as chips and transistors may fail.
>>Power outages: SSDs are subject to damaged file integrity if they are reading or writing during power interruptions.
Enterprise performance SSD drives support greater read-write workloads and have a longer expected service life.
Enterprise performance SSDs provide high endurance and support up to 10 full-drive write operations per day. These SSDs are targeted at write-centric I/O applications such as caching, online transaction processing (OLTP), data warehousing, and virtual desktop infrastructure (VDI).
Enterprise value SSDs provide low endurance and support up to 1 full-drive write operation per day. These SSDs are targeted at read-centric I/O applications such as OS boot, streaming media, and collaboration.
Oftentimes datacenter SSDs use model numbers, custom model numbers, and etc. There are a few major implications. Many of the datacenter drives are not reviewed by major sites and doing pre-purchase research can be a frustrating trip through Google.
The following controller options can be configured with virtual disks to accelerate write and read performance and provide data integrity:
>>Strip (block) size
>>Disk cache policy
>>I/O cache policy
Enterprise grade drives typically are much more expensive, and only have 3 real differences, firstly higher permitted normal operating temperature (for Kingston 55c vs 40c) which unless your putting it in a crawlspace or wardrobe without ventilation, doesn’t make a difference to anyone without a data center. And the second thing is a higher Unrecoverable Bit Read Error (UBRE) thats normally stated as around ten times higher, (for Kingston at 1.11 Petabytes vs only 0.11 Petabytes), which on paper (in many real world tests consumer drives manage much more similarly than this) matters enormously if you plan to use them in an array, but not so much as JBOD.
Finally they have a higher rated Mean Time Before Failure (in Kingston’s case 2x, at 2 million hours).
At Tekmart Africa, we understand these considerations in different data centre ssds' requirement scenarios. If unsure of the correct ssds for your datacenter project implementation, please drop us a mail and one of our solutions consultant will gladly assist with your purchase.
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