VM Tuning & Best PracticesLoic Grange, Principal Architect

John Kuo, Technical Account Manager

First Thing First…• Tableau minimum requirements and recommendations assume bare

metal physical servers, NOT VM’s.• Scalability testing assumes bare metal physical servers as well.

Dedicated Resources RequiredTableau Server is resource-intensive and latency-sensitive due to its interactive nature

• Dedicated Resources Required– Dedicated vCPU

– 100% dedicated vCPU allocation – should not be pooled or shared.– Core count is based on "physical" cores. Physical cores can represent actual server hardware

or cores on a virtual machine (VM). Hyper-threading is ignored.– Dedicated RAM

– Fully (100%) pre-allocated, no pooling or sharing, no dynamic RAM.– Contiguous on the host server.

– Disk– Write speed is often the bottle neck, faster the better!– 150MB/s or less = BAD– 250MB/s+ WRITE = GOOD– 400MB/s to 1GB/s+ = GREAT– 250MB/s Write & 1GB/s Read = Good performance– Tiered SAN: Tableau should be on higher tier with better IO than typical storage level tier.– No underlying network attached storage (NAS) for disk.

• Poorly tuned VM’s Poor performance Wasted $$ on core purchases

Backup & Restore• There’s one and only one Tableau supported way to create a Tableau Server backup

– From http://kb.tableau.com/articles/knowledgebase/server-maintenanceImportant: You can only use backups made with the tabadmin backup command when restoring Tableau Server data. Database backups made in other ways, and virtual machine snapshots are not valid sources for restoring Tableau Server.– Other ways may or may not work. Tableau cannot provide help or support.

• DEFINITELY NOT SUPPORTED– VMotion

– Breaks Tableau’s underlying licensing technology– Assign Tableau to static/dedicated hosts instead

– VM Snapshot

VM Tuning Tips Directly From VMWare

• Performance Best Practices for vSphere 5.5 (http://www.vmware.com/pdf/Perf_Best_Practices_vSphere5.5.pdf)

– See page 17 for recommended BIOS setting• Deploying Extremely Latency-Sensitive Applications in vSphere 5.5

(http://www.vmware.com/files/pdf/techpaper/latency-sensitive-perf-vsphere55.pdf)– See page 15 for best practices for latency-sensitive applications

• Upgrade network adapter driver in VM cluster• From a VMWare Technical Account Manager:What I recommend to my other customers besides what is spelled out in the first guide is to set Power Management to Max Performance and to disable C1E States and C-States. This ensures that the server hardware is always running at its maximum performance capabilities. That way no matter what application comes your way, you are getting the most out of the iron. From my perspective you never know what type of apps you are being asked to support in a virtual environment. You are just getting requests for VMs with certain characteristics, CPUs, RAM, etc… You are not being told, this application is sensitive to latency, or has high I/O characteristics. Usually you get this info after there is a problem. By performing the above steps, you may still have to tweak some VM settings, but you will not have to tweak the underlying iron.

Other Considerations• Virus Scan can impact performance

– Improve Performance by using antivirus exclusions• Network latency between worker machines should be less than 10ms.• Single network hop between servers (contiguous network access).• Tableau can advise VM best practices but cannot help with actual configuration.

Please contact your VM vendor for assistance.