I thought we were on 5.5U3, but that is our VDI hosts only. These hosts are ESX5.5U1. We will be moving to 6.0 within the next several weeks.
The system is using the cfq scheduler. I have read that an IO scheduler like noop is better for flash as it doesn't need to waste time reorganizing IO because the physical movement is no longer a concern. But again, when it comes to reads, it still may come from a spinning disk. I wish I could tell where the read was coming from (Tier 1, 2 or 3), perhaps 95% is coming from SSD and the scheduler might still make a difference.
I will review and make adjustments to the READAHEAD value.
edtieseler
2 Posts
0
September 16th, 2016 12:00
Thanks Don,
I thought we were on 5.5U3, but that is our VDI hosts only. These hosts are ESX5.5U1. We will be moving to 6.0 within the next several weeks.
The system is using the cfq scheduler. I have read that an IO scheduler like noop is better for flash as it doesn't need to waste time reorganizing IO because the physical movement is no longer a concern. But again, when it comes to reads, it still may come from a spinning disk. I wish I could tell where the read was coming from (Tier 1, 2 or 3), perhaps 95% is coming from SSD and the scheduler might still make a difference.
I will review and make adjustments to the READAHEAD value.
I appreciate your input so far.