Dan
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SQL in a VM performance question
I am currently running a physical server for my SQL 2012 R2 box. I'm planning to visualize the box to my HP SAN.
I bought a new enclosure just for this SQL VM. I've partitioned the enclosure with 3 different partitions, one for the OS, one for the data and one for the Logs. The OS and Logs volume are raid 1. The Data volume is raid 6.
I ran a performance test using the Crystal Disk Mark software: http://crystalmark.info/software/CrystalDiskMark/index-e.html
I ran the tests on my physical server and also on the raid 6 and raid 1 volumes as well.
I'm trying to figure out if there's a major difference between the raid 6 and raid 1, as I would like to keep my data with raid 6, so I don't have to use raid 10, or I will lose to much storage.
Looks to me like the physical server is faster than the VM, but there isn't much difference between raid 6 and raid 1.
Is this correct?
Will it be adequate to use raid 6 for my data volume, instead of using raid 10?, as raid 1 didn't make a big difference?
I bought a new enclosure just for this SQL VM. I've partitioned the enclosure with 3 different partitions, one for the OS, one for the data and one for the Logs. The OS and Logs volume are raid 1. The Data volume is raid 6.
I ran a performance test using the Crystal Disk Mark software: http://crystalmark.info/software/CrystalDiskMark/index-e.html
I ran the tests on my physical server and also on the raid 6 and raid 1 volumes as well.
I'm trying to figure out if there's a major difference between the raid 6 and raid 1, as I would like to keep my data with raid 6, so I don't have to use raid 10, or I will lose to much storage.
Looks to me like the physical server is faster than the VM, but there isn't much difference between raid 6 and raid 1.
Is this correct?
Will it be adequate to use raid 6 for my data volume, instead of using raid 10?, as raid 1 didn't make a big difference?
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Use Diskspd to benchmark your different IO scenarios.
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it depends - -in your case RAID 6 could be good.. Are you using SAN, EMC storage ?
check
Disk Partition Alignment Best Practices for SQL Server
https://technet.microsoft.com/en-us/library/dd758814(v=sql.100).aspx
MICROSOFT SQL SERVER BEST PRACTICES
AND DESIGN GUIDELINES FOR EMC
STORAGE
https://www.emc.com/collateral/white-papers/h12341-sqlserver-bp-wp.pdf
Architecting Microsoft SQL Server
on VMware vSphere
http://www.vmware.com/content/dam/digitalmarketing/vmware/en/pdf/solutions/sql-server-on-vmware-best-practices-guide.pdf
check
Disk Partition Alignment Best Practices for SQL Server
https://technet.microsoft.com/en-us/library/dd758814(v=sql.100).aspx
MICROSOFT SQL SERVER BEST PRACTICES
AND DESIGN GUIDELINES FOR EMC
STORAGE
https://www.emc.com/collateral/white-papers/h12341-sqlserver-bp-wp.pdf
Architecting Microsoft SQL Server
on VMware vSphere
http://www.vmware.com/content/dam/digitalmarketing/vmware/en/pdf/solutions/sql-server-on-vmware-best-practices-guide.pdf
It looks like the sequential san speeds are limited by gigabit Ethernet (120MB/s), is that how it's connected? Like was said in the first comment, you only care about the 4K numbers not the sequential anyway so you will be fine.
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ASKER
Thanks everyone for the input.
I have an HP SAN 2332i
The enclosure I'm using has 450Gb SAS drives, 15K rpm
Some of you mentioned that the SAN will be faster than the physical box, but I wonder how that's possible when the numbers show opposite? I guess I'm not reading the numbers correctly?
The raid 6 volume has 8 drives in the array.
I'm also running HP servers, proliant, DL360 G7 and G8 servers. I'm planning on only running my SQL sever on one physical servery, so I can give it like 100GB or so, as I have 128Gb on the physical server.
I'm only going to run my SQL server on this enclosure.
I created 1 volume for the OS, 2 drives, raid 1
I created 1 volume for the data, 8 drives, raid 6
I created 1 volume for logs, 2 drives, raid 1
I am using ISCSI to connect my SAN and servers. I am using dual NICs, so I think I'm getting up to 2Gb/s.
I tried using dskpsd, but it gave me errors, so I couldn't get it to run.
I'm not sure how to align the disks with block sizes of 64K.
I have an HP SAN 2332i
The enclosure I'm using has 450Gb SAS drives, 15K rpm
Some of you mentioned that the SAN will be faster than the physical box, but I wonder how that's possible when the numbers show opposite? I guess I'm not reading the numbers correctly?
The raid 6 volume has 8 drives in the array.
I'm also running HP servers, proliant, DL360 G7 and G8 servers. I'm planning on only running my SQL sever on one physical servery, so I can give it like 100GB or so, as I have 128Gb on the physical server.
I'm only going to run my SQL server on this enclosure.
I created 1 volume for the OS, 2 drives, raid 1
I created 1 volume for the data, 8 drives, raid 6
I created 1 volume for logs, 2 drives, raid 1
I am using ISCSI to connect my SAN and servers. I am using dual NICs, so I think I'm getting up to 2Gb/s.
I tried using dskpsd, but it gave me errors, so I couldn't get it to run.
I'm not sure how to align the disks with block sizes of 64K.
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If you care at all about the performance, use SSD. PERIOD. END OF STORY. A single SSD will outperform 100 15K SAS drives in RAID 0, and be cheaper.
ASKER
I know, and I agree, but my HP SAN does NOT support SSD's.
The SAN is about 5 to 6 years old, if not older.
The SAN is about 5 to 6 years old, if not older.
If your SAN is so old, why are you looking to use it for this application? Are you looking to possibly improve availability via hypervisor clustering?
Just putting SSD into the physical server now will speed it up tremendously, and would keep you at the same availability levels you have now. You can then decide whether or not to virtualize it on the same hardware or different hardware.
Just putting SSD into the physical server now will speed it up tremendously, and would keep you at the same availability levels you have now. You can then decide whether or not to virtualize it on the same hardware or different hardware.
ASKER
Yes, I am using hyper-V, in a cluster environment.
A new equiavelant SAN is about 15 to 25k, so I think we'll try to get another 3-4 years out of our current SAN before replacing it.
A new equiavelant SAN is about 15 to 25k, so I think we'll try to get another 3-4 years out of our current SAN before replacing it.
>Some of you mentioned that the SAN will be faster than the physical box, but I wonder how that's possible when the numbers show opposite? I guess I'm not reading the numbers correctly?
As I mentioned in my first post, the columns of intrest are 4K and 4K Q32T1, which is equivalent to IOPS. Databases need a lot of IOPS. Ignore the SEQ columns because databases usually don't do much sequential IO. Look at my first post for details.
The 4K IOPS RAID6 numbers are higher for the SAN than they are for physical server, so no need to worry about RAID6.
Just one important question you need to ask yourself: is performance adequate on the current physical server? If the answer is yes then there's no need to spend money for a new SAN or 10Gbit ethernet because the SAN box you have will be faster than the physical storage. You don't mention any existing performance issues so sometimes good is good enough.
As I mentioned in my first post, the columns of intrest are 4K and 4K Q32T1, which is equivalent to IOPS. Databases need a lot of IOPS. Ignore the SEQ columns because databases usually don't do much sequential IO. Look at my first post for details.
The 4K IOPS RAID6 numbers are higher for the SAN than they are for physical server, so no need to worry about RAID6.
Just one important question you need to ask yourself: is performance adequate on the current physical server? If the answer is yes then there's no need to spend money for a new SAN or 10Gbit ethernet because the SAN box you have will be faster than the physical storage. You don't mention any existing performance issues so sometimes good is good enough.
ASKER
Thanks Everyone for your help and input.
Sequential IO is not important, because SQL server rarely does sequential IO (except perhaps for backups/database verification).
I would say that the VM in combination with your SAN can handle about 2x to 4x the IO the physical box can. This is not unusual as a SAN often has more spindles and cache than a physical server with internal storage.
If your SQL server has a high load, you may see a speed boost when moving to this setup. RAID6 has an impact on 4K write speed compared to RAID 1, but again this will not impact you as this is still faster than your physical box.