Rapid adoption of virtualization technologies has led to increased utilization of physical resour... more Rapid adoption of virtualization technologies has led to increased utilization of physical resources, which are multiplexed among numerous workloads with varying demands and importance. Virtualization has also accelerated the deployment of shared storage systems, which offer many advantages in such environments. Effective resource management for shared storage systems is challenging, even in research systems with complete end-to-end control over all system components. Commercially-available storage arrays typically offer only limited, proprietary support for controlling service rates, which is insufficient for isolating workloads sharing the same storage volume or LUN.
workloads is the first step in tuning disk subsystem performance. This paper presents an efficien... more workloads is the first step in tuning disk subsystem performance. This paper presents an efficient implementation of disk I/O workload characterization using online histograms in a virtual machine hypervisor-VMware ESX Server. This technique allows transparent and online collection of essential workload characteristics for arbitrary, unmodified operating system instances running in virtual machines. For analysis that cannot be done efficiently online, we provide a virtual SCSI command tracing framework. Our online histograms encompass essential disk I/O performance metrics including I/O block size, latency, spatial locality, I/O interarrival period and active queue depth. We demonstrate our technique on workloads of Filebench, DBT-2 and large file copy running in virtual machines and provide an analysis of the differences between ZFS and UFS filesystems on Solaris. We show that our implementation introduces negligible overheads in CPU, memory and latency and yet is able to capture essential workload characteristics.
Server virtualization is accelerating the already existing need for shared storage area network (... more Server virtualization is accelerating the already existing need for shared storage area network (SAN) infrastructure for the associated benefits of migration, flexible management and economies of sharing. Understanding the characteristics of a workload in terms of access locality, IO sizes, read write ratio etc. is crucial for effective placement and consolidation. The lack of visibility into workload details and placement often leads to design inefficiencies and overprovisioning.
Rapid adoption of virtualization technologies has led to increased utilization of physical resour... more Rapid adoption of virtualization technologies has led to increased utilization of physical resources, which are multiplexed among numerous workloads with varying demands and importance. Virtualization has also accelerated the deployment of shared storage systems, which offer many advantages in such environments. Effective resource management for shared storage systems is challenging, even in research systems with complete end-to-end control over all system components. Commercially-available storage arrays typically offer only limited, proprietary support for controlling service rates, which is insufficient for isolating workloads sharing the same storage volume or LUN.
workloads is the first step in tuning disk subsystem performance. This paper presents an efficien... more workloads is the first step in tuning disk subsystem performance. This paper presents an efficient implementation of disk I/O workload characterization using online histograms in a virtual machine hypervisor-VMware ESX Server. This technique allows transparent and online collection of essential workload characteristics for arbitrary, unmodified operating system instances running in virtual machines. For analysis that cannot be done efficiently online, we provide a virtual SCSI command tracing framework. Our online histograms encompass essential disk I/O performance metrics including I/O block size, latency, spatial locality, I/O interarrival period and active queue depth. We demonstrate our technique on workloads of Filebench, DBT-2 and large file copy running in virtual machines and provide an analysis of the differences between ZFS and UFS filesystems on Solaris. We show that our implementation introduces negligible overheads in CPU, memory and latency and yet is able to capture essential workload characteristics.
Server virtualization is accelerating the already existing need for shared storage area network (... more Server virtualization is accelerating the already existing need for shared storage area network (SAN) infrastructure for the associated benefits of migration, flexible management and economies of sharing. Understanding the characteristics of a workload in terms of access locality, IO sizes, read write ratio etc. is crucial for effective placement and consolidation. The lack of visibility into workload details and placement often leads to design inefficiencies and overprovisioning.
Uploads
Papers by irfan ahmAD