[MarkLogic Dev General] Azure/Hyper-V virtual disk write cache policy

Will Thompson wthompson at oconnors.com
Wed Feb 1 08:42:01 PST 2017


In Azure or Hyper-V-based VMs, the write caching policy for a virtual disk always displays as enabled (and it can't be changed), regardless of whether or not the system hosting the virtual disk is really configured to cache writes. However, there is a second option underneath it to disable Windows buffer-flushing:

[x] Enable Write Caching on the device
    [ ] Turn off Windows write-cache buffer flushing on the device 

For a physical disk with write caching disabled, this option would be greyed out, but for virtual disks with write caching disabled, it's not. This article claims that the box *should* be checked in the latter case because it can improve application performance without affecting data integrity:

http://www.virtualizationadmin.com/articles-tutorials/microsoft-hyper-v-articles/management/hyper-v-optimization-tips-part1.html

I have not seen this suggested anywhere else. Can anyone running ML on Azure or Hyper-V share their write cache policy settings or comment on this claim? 

Thank you,

Will


More information about the General mailing list