When I joined Tech Marketing in February of this year my first task literally was the ESX System Analyzer. I was part of the team who developed the specs and test the app, but the main driving force behind the tool was my colleague Kyle Gleed (@VMwareESXi). The tool / fling was designed specifically to help people migrate from ESX [...]

There has been a lot of discussion in the past around Disk.SchedNumReqOutstanding and what the value should be and how it relates to the Queue Depth. Jason Boche wrote a whole article about when Disk.SchedNumReqOutstanding (DSNRO) is used and when not and I guess I would explain it as follows: When two or more virtual machines are issuing I/Os to [...]

I had this question coincidentally two times of the last 3 weeks and I figured that it couldn’t hurt explaining it here as well. The question on the VMTN community was as follows: on 13 sec: a host which hears from none of the partners will ping the isolation address on 14 sec: if no reply from isolation address it [...]

Lately I have been thinking about the future of servers and more specifically the design around servers. Servers are more and more heading towards these massive beasts with all sorts of options that many might not need, but end up paying for as they are already bolted on. On the other hand you have these massive blade chassis that will [...]

We had a discussion internally about ESX/ESXi caching I/Os. In particular this discussion was around caching of writes  as a customer was concerned about consistency of their data. I fully understand that they are concerned and I know in the past some vendors were doing write caching however VMware does not do this for obvious reasons. Although performance is important [...]

When we wrote the HA/DRS book both Frank and I were still very much in an “ESX Classic” mindset. Over the last weeks I had questions around resilient network configurations for ESXi. I referred people back to the book but the comments that I got were that the examples were very much ESX Classic instead of ESXi. Now in my [...]

I’ve seen this myth floating around from time to time and as I never publicly wrote about it I figured it was time to write an article to debunk this myth. The question that is often posed is if thin disks will hurt performance due to fragmentation of the blocks allocated on the VMFS volume. I guess we need to [...]