SSD for server
Some details about the market of SSD for server solutions
HDD 10-15K rpm hard drives are becoming obsolete. Their mechanical nature does not leave them a chance to confront SSD capabilities in enterprise applications. SSD for server with NAND flash memory occupied the top of corporate data storage pyramids and continue to win from HDD approaches to them. It is understood that the total emergency replacement HDD to the SSD for server will not happen for several reasons:
many storage segments are indifferent to the main SSD trump - performance but sensitive to the volume / price;
HDD at 7200 rpm has high capacity and low unit cost $ / GB;
server market is conservative.
Needless to say, the SSD is faster. Delays in supplying read / write data on a HDD rotating magnetic surfaces (seek / latency) irresistible. In order to achieve a decent performance with the data on the HDD resorted to parallelizing applications in multi-groups, cache I / O requests by means of controllers and operating systems - and still helps weakly.
HDD is good for writing large files by sequential blocks. With a minimum of moving the head between tracks is reduced latency data access. But as soon as the drive is filled with data, large files are written pieces - where there is a free sector. No matter how improve read / write algorithms, fragmented data remain HDD scourge.
The role of SSD for server
Where high performance requirements are must, and the amount of data is relatively small, there SSD for server and displace SAS HDD: in database servers, for placing the swap file and placement of temporary tables, as a cache pool tiered storage systems managed by the OS even though RAID- controllers.
In modern data storage systems data loss risks are minimized, the failure of a single disk is usually fraught with only a temporary degradation of performance in the reconstruction of the array after a disk replacement by a new one. However, threats to data necessary to be considered.
Official statistics of HDD and SSD for server failure manufacturers do not publish. As it usually happens with young technologies, storage in NAND flash memory is surrounded by myths and fears. Reasons for these are, as a rule, ignorance and improper use of SSD for server.
For data centers that operate hundreds of the HDD, the replacement of most of them on a dozen or two SSD saves space, dramatically reduces capital equipment costs and operating expenses for power / cooling. And even at the level of the design of the server, a simple cut optimizes its owner the costs of achieving goals.