Andrew Calvett's SQL Server Blog

I have been reading about Server Message Block (SMB) 3 and thought to myself it would be good to remind people about SMB 2 as many systems have not upgraded to Windows 2008 to take advantage of it.

For more background on SMB, please see this article.

When Microsoft introduced SMB 2 they pretty much started again. During one of my recent migrations I found that the file copy improvements from Windows 2008 R2 have literally been jaw dropping and the highlights are.

• We see a 45 times improvement in throughput for file transfer across the wan!
• We can now transfer data at a rate of around  5.5 gb a minute where as previously we struggled to sustain 1.5gb a minute.

Below are some statistics gathered for transferring 1.2gb’s between the USA & London.

Prior to running each test trace routes were run to confirm number of hops and latency across the pond was the same for each server.

Files used to test were a compressed SQL Backup file and an SSAS data file.

I find these results very exciting from a DBA perspective and below are a few operations that instantly come to mind as benefiting.

• Synchronising large SSAS cubes across the WAN. Previously i probably would not have considered this for my “larger clients” but if you add this performance gain to the multithreaded robocopy we have a winner…
• Copying large backups across the WAN to initialise replication was often painful and rarely top of the list. Think again.
• Log shipping across high latency links could now become viable. (Yes, i said log shipping. Don’t go all mirroring on me there are still use cases )

One of the considerations to achieving this performance is both hosts must be running a compatible OS, that is W2K8 or above and Windows Vista or above.

There is an excellent paper by Netapp on SMB2 which echoes the findings in this blog and goes into much more detail which i would recommend reading.

So am i excited about SMB3? Absolutely! Microsoft have pulled another blinder and if you want to find out more about SMB3 then check out this post which covers pretty much everything you need.