Knowledge Base

To use the utility help diagnose performance issues:

1. Establish an SSH connection to the ESX host.
2. Run the esxtop command.
3. Press d to switch to the storage (disk) adapter resource utilization screen.
4. Using the VMware Infrastructure Client, connect to the ESX host or VMware VirtualCenter Server. In the Configuration > Storage screen, identify the LUN you wish to address. Locate this LUN's vmhba information, vmhbaC:T:L. The numbers in the C, T, and L fields correspond to the CID, TID, and LID values below.
5. Pick an adapter you want to drill into:
   
   ADAPTR CID TID LID WID NCHNS NTGTS NLUNS NVMS
   vmhba0   -   -   -    -     1     5     5   22
   
   Note: You may wish to pick an adapter that has a higher value NVMS (number of virtual machines) or CMDS/s (commands per second).
   
   
6. Press e to populate the Channel ID (CID) field.
   
   Adapter to expand/rollup (adaptr): vmhba0
   ADAPTR CID TID LID  WID NCHNS NTGTS NLUNS NVMS
   vmhba0   0   -   -    -     1     5     5   22
   
   
7. Press a to populate the Target ID (TID) field.
   
   Channel name to expand/rollup (adapter:cid) - vmhba0:0
   ADAPTR CID TID LID  WID NCHNS NTGTS NLUNS NVMS
   vmhba0   0   1   -    -     1     1     1    6
   
   
8. Press t to populate the LUN ID (LID) field.
   
   Target name to expand/rollup (adapter:cid:tid) - vmhba0:0:1
   ADAPTR CID TID LID  WID NCHNS NTGTS NLUNS NVMS AQLEN LQLEN WQLEN ACTV QUED %USD  LOAD
   vmhba0   0   1   0    -     1     1     1    6   253    32     0    0    0    0  0.00
   
   Note: After pressing Enter, the ACTV, QUED, %USD , and LOAD values populate.
   
   
9. Press l to populate the World ID (WID) field.
   
   Lun name to expand/rollup (adapter:cid:tid:lid) - vmhba0:0:1:0
   ADAPTR CID TID LID  WID NCHNS NTGTS NLUNS NVMS AQLEN LQLEN WQLEN ACTV QUED %USD  LOAD   CMDS/s
   vmhba0   0   1   0 1077     0     0     0    1   253    64    32    1    0    3  0.03   141.13
   
   From this, you can see that the world ID (WID) 1077 is processing 141.13 commands per second.
   
   
10. Press Ctrl+C to exit esxtop.

To associate the virtual machine world number (WID) with a name, see Mapping a virtual machine world number to a virtual machine name (1001101).

• Worlds listed which are not shown in vm-support -x may not be user created worlds, like 1024 which is the service console.
• While in esxtop you can press f (for Field) to add or remove other columns from view.
• While in esxtop you can press o to change the order of the columns.
• While in esxtop you may press # to change the number of rows to show, otherwise, it uses window size detection.
• For more information on what the fields mean, type man esxtop .