By monitoring IO requests at the vDisk and VM level and integrating with vCenter APIs, Tintri VMstore knows the identity of the corresponding VM for each IO request, and can determine if latency occurs at the hypervisor, network, or storage levels.
For each VM and vDisk stored on the system, IT teams can use Tintri VMstore to instantly visualize where potential performance issues may exist across the stack. Latency statistics are displayed in an intuitive format. In an instant administrators can see the bottleneck, rather than trying to deduce the location from indirect measurements and time-consuming detective work.
Administrators can detect trends with data from VMstore and individual VMs, all without the added complexity of installing and maintaining separate software. This built-in insight can reduce costs and simplify planning activities, especially around virtualizing IO-intensive critical applications and end-user desktops.
To handle monitoring and reporting across multiple VMstore systems, Tintri created Tintri Global Center (Figure 5). Built on a solid architectural foundation capable of supporting more than one million VMs, Tintri Global Center is an intuitive, centralized control platform that lets administrators monitor and administer multiple, geographically-distributed VMstore systems as one. IT administrators can view and create summary reports across all or a group of VMstore systems, with in-depth information on storage performance (IOPS, latency, throughput), capacity, vCenter clusters, host status, protection status and more.
Figure 5. Trintri Global Center.
In addition to summary information presented at a glance, Tintri Global Center also provides the ability to filter and display results, including by individual VMstore systems and specific VMs, for easy troubleshooting.
Handling Spikes In Device Latencies
Tintri VMstore integrates flash as a first-class storage medium rather than as a bolt-on cache or tier, to fully leverage continued improvement in flash price and performance. Using flash as an intelligent, highly granular resource — combined with inline deduplication, compression and a unique flash/disk file system — enables Tintri VMstore to radically alter the economics of server virtualization.
Tintri’s innovative FlashFirst design addresses MLC flash problems that previously made it unsuitable for enterprise environments. Flash suffers from high levels of write amplification due to the asymmetry between the size of blocks being written and the size of erasure blocks for flash. Unchecked, this reduces random write throughput by more than 100 times, introduces latency spikes and dramatically reduces flash lifetime.
FlashFirst design uses a variety of techniques including deduplication, compression, analysis of IO, wear leveling, GC algorithms and SMART monitoring of flash devices and dual parity RAID 6 to handle write amplification, ensure longevity and safeguard against failures.
VM QoS: Tintri VMstore is designed to support a mixed workload of hundreds of VMs, each with a unique IO configuration. Additionally, as volumes of traffic ebb and flow, VMstore through its FlashFirst design analyzes and tracks the IO for each VM, delivering consistent performance where it is needed.
This enables VMstore to isolate the VMs, queue, and allocate critical system resources such as networking, flash/SSDs and system processing to individual VMs. Tintri VMstore’s QoS capability is complementary to VMware’s performance management capability. The result is consistent performance where needed. And all of VM QoS functionality is transparent, so there is no need to manually tune the array or perform any administrative touch.
QoS is critical when storage must support high-performance databases generating plenty of IO alongside latency-sensitive virtual desktops. This is commonly referred to as the noisy neighbor problem in traditional storage architectures that are flash-only and lack VM-granular QoS. Tintri VMstore ensures database IO does not starve the virtual desktops, making it possible to have thousands of VMs served from the same storage system.