132 reputation
8
bio website sgdk2.sf.net
location Bloomington, MN
age 39
visits member for 4 years, 3 months
seen Jan 18 at 13:18
Professionally, I use VB.NET for UI and data framework development to support enterprise resource planning software. As a hobby, I use C# to develop a 2-D scrolling game IDE and framework Scrolling Game Development Kit.

Oct
9
awarded  Popular Question
Feb
2
comment How do I delete a differential backup?
Any friendlier way to do this through Management Studio?
Sep
20
comment Certain SQL queries performing very poorly in ESXI hosted environment
As expected, enabling write caching totally resolved the performance issue we were looking at.
Sep
20
awarded  Scholar
Sep
20
accepted Certain SQL queries performing very poorly in ESXI hosted environment
Sep
20
comment Certain SQL queries performing very poorly in ESXI hosted environment
As it turns out, the reason for the poor performance is specific to our server model as I described in the latest edit to the question. Thanks for leading us down the right path.
Sep
20
revised Certain SQL queries performing very poorly in ESXI hosted environment
added 352 characters in body
Sep
20
comment Certain SQL queries performing very poorly in ESXI hosted environment
The thing that had us so puzzled is that we are using local storage, and it's performing worse than the virtual systems that are on a SAN. I think we need to look at the hardware statistics of the drives in use, and perhaps the RAID configuration. Hopefully now that we have a work day, we'll be able to review some of that.
Sep
20
awarded  Commentator
Sep
20
comment Certain SQL queries performing very poorly in ESXI hosted environment
We have been searching for the source of this performance problem for weeks and have already looked at RAM, and a number of other factors. This test, while not very robust, has led us to what I feel is the source of the problem -- the I/O latency. It appears to be an order of magnitude higher than it should be, which seems to fit all the observations. Sure, more testing would be a good idea too, but I couldn't figure out what the test I was already running was pointing at. Now I see.
Sep
19
revised Certain SQL queries performing very poorly in ESXI hosted environment
added 157 characters in body
Sep
19
awarded  Editor
Sep
19
comment Certain SQL queries performing very poorly in ESXI hosted environment
Can you say more about RAID5 across 1 TB disks not being optimal? Do you think that would account for a significant portion of the performance loss we're seeing (after reviewing the probable statistic at fault here in the first answer)?
Sep
19
revised Certain SQL queries performing very poorly in ESXI hosted environment
added 753 characters in body
Sep
19
comment Certain SQL queries performing very poorly in ESXI hosted environment
I suspected something like this after reviewing my results. So I guess the question becomes "is it normal for virtual environments to have such a huge difference in I/O latency, or should I be able to optimize these environments?" I'll update my question with this and other details.
Sep
18
comment Certain SQL queries performing very poorly in ESXI hosted environment
1. VMWare Tools is installed. 2. The purpose of this question is not to optimize the database, which is just a symptom of the problem, but to get our virtual environments' performances comparable to physical environments. So adding indexes only works around my sample demonstration of the problem. It doesn't fix it.
Sep
18
comment Certain SQL queries performing very poorly in ESXI hosted environment
I tried running iometer in a guest environment and never got past "Preparing disks... \\?\Volume{efb8d326-c010-11df-9d3c-806e6f6e6963} preparing."
Sep
18
comment Certain SQL queries performing very poorly in ESXI hosted environment
Is that something that would be run on the host machine? If so, it will have to wait a while because I have never seen the hardware myself and don't have access to it (will need assistance). Is it safe to do that while the host and guest environments are running?
Sep
18
comment Certain SQL queries performing very poorly in ESXI hosted environment
Run it on what? Is it even possible to run things on the ESXi host? Wouldn't we have to remove ESXi and install an OS?
Sep
18
asked Certain SQL queries performing very poorly in ESXI hosted environment