So I wish there was one consolidated doc of settings to change for ESXi 5.1 and EqualLogic. Anyone out there have more settings please let me know!!
To start from here http://en.community.dell.com/techcenter/storage/f/4466/t/19459676.aspx
1.) Delayed ACK DISABLED
2.) Large Receive Offload DISABLED
3.) Make sure they are using either VMware Round Robin (with IOs per path changed to 3), or preferably MEM 1.1.0.
4.) Set Login_timeout to 15 or 30 seconds
I contacted EqualLogic support and they replied:
Solution Title HOWTO: Disabling TCP Delayed ACK may improve read performance with ESX 3.x/4.x/5.x software iSCSI initiator.Solution Details ESX allows you to disable the delayed ACK on your ESX host through a configuration option and may improve the read performance of storage attached to ESX software through the iSCSI initiator. PLEASE NOTE: this change will require a reboot of the ESX server to take effect.
Disabling Delayed Ack in ESX 4.0, 4.1, and 5.x
1. Log in to the vSphere Client and select the host.
2. Navigate to the Configuration tab.
3. Select Storage Adapters.
4. Select the iSCSI vmhba to be modified.
5. Click Properties.
6. Modify the delayed Ack setting using the option that best matches your site’s needs.
Choose one of the below options, I, II or II, then move on to step 7 after making the changes:
Modify the delayed Ack setting on a discovery address (recommended).
A. On a discovery address, select the Dynamic Discovery tab.
B. Select the Server Address tab.
C. Click Settings.
D. Click Advanced.
7. In the Advanced Settings dialog box, scroll down to the delayed Ack setting.
8. Uncheck Inherit From parent. (Does not apply for Global modification of delayed Ack)
9. Uncheck DelayedAck.
10. Reboot the ESX host.
One thing about Delayed ACK, is that you have to verify that the change took place. If you just change it, it appears that only new LUNs will inherit the value. (disable) I find that, while in maint mode, removing the discovery address and any discovered targets (in static discovery tab), then disabling Delayed ACK and re-add in Discovery Address and rescan resolves this.
At the ESX console run: #vmkiscsid –dump-db | grep Delayed All the entries should end with =’0′ for disabled. ( note that is a – – two dashes before the dump-db silly WP font)
I ran it and experienced the same, only some of the connections had the DelayedAck set correctly. So definitely remove the discovery address and static targets to fix.
To disable LRO from http://communities.vmware.com/thread/419234
HOWTO: Disable Large Receive Offload (LRO) in ESX v4/v5
Within VMware, the following command will query the current LRO value.# esxcfg-advcfg -g /Net/TcpipDefLROEnabledTo set the LRO value to zero (disabled):# esxcfg-advcfg -s 0 /Net/TcpipDefLROEnabledNOTE: a server reboot is required.
Info on changing LRO in the Guest network.
To disable LRO, follow this procedure:
Your guest VMs should now have normal TCP networking performance.
Set Login Time Out
This vmware 5.1 document points to this KB article http://kb.vmware.com/kb/2007829
- Go to Storage Adapters > iSCSI Software Adapter > Properties.
- Select Advanced and scroll down to LoginTimeout.
- Change the value from 5 seconds to a larger value, such as 15 or 30 seconds.
On second review the Official Documentation for the EqualLogic MEM (Rev 1.2, which covers vSphere 5.1)
Deployment Considerations: iSCSI Login Timeout on vSphere 5.1 and5.0
The default value of 5 seconds for iSCSI logins on vSphere 5.x is too short in some
circumstances. For example: In a large configuration where the number of iSCSI
sessions to the array is close to the limit of 1024 per pool. If a severe network
disruption were to occur, such as the loss of a network switch, a large number of iSCSI
sessions will need to be reestablished. With such a large number of logins occurring,
some logins will not be completely processed within the 5 second default timeout
Dell therefore recommends applying patch ESXi500-201112001 and increasing the ESXi
5.0 iSCSI Login Timeout to 60 seconds to provide the maximum amount of time for
such large numbers of logins to occur.
If the patch is installed prior to installing the EqualLogic MEM, the MEM installer will
automatically set the iSCSI Login Timeout to the Dell recommended value of 60
Automatically setup is nice in theory but doesn’t appear to work with ESX5.1 ??? I had to set mine to 60 manually
I was able to find these three recommendations under the support portal under here https://support.equallogic.com/support/solutions.aspx?id=1444