Virtualization and consolidation in server applications to achieve remarkable results, but all the virtual machines are installed to a server to bring a little trouble along the path of memory.
For the data center, the virtual environment storage I / O bottleneck is a constantly increasing and long-term problem, because the memory controller and the first equipment will be issued a large number of virtual machine I / O requests flooded, causing processing delays.
To find a solution to solve the I / O disorder in the data storage has become a top priority for manufacturers. IBM, NetApp, BlueArc, and Panasas and other manufacturers are actively developing unique innovative technology to solve this problem.
NAS and SAN solutions provider NetApp virtualization solutions and alliances, said Senior Director Jim Sangster, virtual servers and NAS or SAN storage systems, the core issue is the number of server applications running on much more than physical servers, resulting in storage I / O limited.
Sangster said that each application would require a I / O resources. He said: "A virtual server may be required from 6 to 10 ports, the I / O request is the physical server 2 to 3 times. "
The more ports to connect more and more cable used to connect the more. Increase storage capacity and can not solve this problem, because the real need is for better connectivity.
Most virtualization solutions to support NAS, Fibre Channel and iSCSI storage, but not all of the virtual machine can be directly connected to the storage system. When a virtual machine can not be directly connected with the storage system, the most common result is that the response time longer, if the situation worse, then there will be storage operation error.
In the virtual environment, there are four storage-related major bottlenecks, which are: 1, virtual server applications over (oversubscription); 2, disk drive and target storage system for excess; 3, SAN or NAS network of over-subscription ; and 4, the target storage port oversubscribed. Although the application over the more common in IT, but the over-subscription in the calculation errors may cause serious I / O data flow obstruction.
Big Blue's SAN solution
IBM's XIV storage experts Kem Clawson said the alliance, IBM has tried to develop a new type of SAN storage system for the same virtual environment I / O problem.
Clawson said: "We deal with XIV's approach is to develop a general store for the use of technology to build a dynamic virtual environment to optimize the system. A large part of the work we do is in the commodity hardware, the development of our solutions to ensure that it can be applied to all circumstances. "
Taneja Group analyst in November 2008 pointed out a technical summary, IBM XIV storage system from the bottom up to improve the performance of various parts of the system.
It said the share of technical summary of the use of 15 12 of disk data blocks or 180 SATA disks, IBM XIV system through a cache provided from 100000IOPS, from the disk to provide 20000IOPS, sustainable sequential read and write bandwidth of 2.4 GBps and 1.4GBps. It is able to provide this level of performance, because the use of intelligent caching algorithm XIV rapid analysis and extraction of the data cache, and thus for each I / O optimized.
BlueArc and Panasas pNFS options
IBM's overall analysis and solution is different, BlueArc, NetApp and Panasas have used different methods to solve the other I / O problem. BlueArc and Panasas parallel network file system, the main (pNFS) technology, which allows users to directly access storage devices, but also in parallel. NetApp is using performance acceleration module called (PAM) technology.
BlueArc's product marketing senior manager Gerard Sample said, pNFS solution eliminates the old NFS server in use today appear in scalability and performance problems. BlueArc's Titan family of products support NAS and SAN.
Sample said, pNFS is an important technology, because it will be based on common standards for the parallel NFS I / O advantages are together.
Sample said: "The parallel I / O's main advantage is that it can provide high application performance and great scalability. "BlueArc's Titan 3200 speed performance can be achieved 1600mbps, I / O performance can be 380000IOPS.
Panasas, director of software architecture, said Brent Welch, Panasas pNFS use of the focus on Intel's latest high-performance solid state disk used ActiveStor products.
Welch said, and the provision of high bandwidth optimization IOPS performance or one-dimensional solution is different, ActiveStor in a synchronization architecture using a variety of storage technologies to simultaneously achieve high bandwidth performance and optimization of IOPS.
Welch said, ActiveStor through cache, SATA 3 solid-state disk and storage resources together in ways that achieve higher levels of performance. This framework provides a distributed data channel balanced I / O, eliminating performance bottlenecks, while achieving the performance of hundreds of GB per second.
NetApp storage using PAM technology to solve I / O problem
NetApp's PAM innovative solutions to attract considerable attention, because it can improve performance while reducing FAS storage system I / O pressure.
NetApp's PAM module is 16GB of card number, you can plug in the PCIe slot to use as a read cache, it can eliminate the high I / O requirements of applications and server blocking question.
Sangster said: "By improving information throughput and delay performance, while reducing the disk is running in the number, PAM can optimize the performance of NetApp storage systems. "
He said: "Configure one or more of the PAM to the I / O brings the important benefit of access to PAM cache can significantly reduce the time required to obtain data. "
He added that many high-performance computing environment, the problem is not capacity, but in the I / O throughput of information, that data is written to disk or from the disk read speed.
Sangster said: "If a data center I / O performance is limited, so IT will be selected each time this card, not only to satisfy the information requirements of throughput, but also to meet the performance requirements. "
To ensure that the storage system into the virtual environment is no longer the weak link, IBM, NetApp, BlueArc, and Panasas innovation in technology has a long way to go.