topic Re: vFlash performance metrics missing in vSphere™ Storage Discussions

vFlash performance metrics missing

Krede — Fri, 01 Nov 2013 12:08:03 GMT

Hi,

I’m playing with the new vFlash feature in my vSphere 5.5 lab. All seems to be working…but – I’m unable to find the new Performance metrics in vSphere Web client (when looking on “virtual disk” on the VM object).

According to http://www.vladan.fr/vflash-read-cache/ I should have three new metrics called:

FlashCacheIOPs

FlashCacheLatency

FlashCacheThroughput

But they are not there.

Any clues out there?

Re: vFlash performance metrics missing

swalker_LST — Thu, 13 Feb 2014 17:04:20 GMT

Me too - I've just upgraded from a fresh installation of vCenter Server 5.1 on Oracle DB, to 5.5b and the counters are missing. I have enabled vFRC on one ESXi 5.5 host (Ent Plus license) and I can use the command line to verify cache information but the counters are not visible in either the C# or Web Clients. Don't seem to find any other information from other people having this issue.

Re: vFlash performance metrics missing

Tom_NL — Fri, 23 May 2014 08:35:12 GMT

We have the same problem here. Does someone have a solution?

Re: vFlash performance metrics missing

WDeignan — Tue, 15 Jul 2014 15:59:04 GMT

In case anybody else finds this thread via Google - the performance counters only seem to appear in the web client after a given VM has been enabled for flash cache for a while. I'm not sure of the exact timing, but when I checked immediately after enabling the VM they were missing. When I checked again the next morning they had appeared and had data.

Re: vFlash performance metrics missing

PeterCr — Thu, 18 Dec 2014 02:18:16 GMT

I've had mixed results with getting vFlash metrics also, some VM's show metrics straight away, some after a couple of hours, some never show.

In ESXi the /var/log/hostd.log there will be messages similar to below indicating a problem.

2014-12-18T02:20:40.023Z [3DF42B70 error 'Statssvc.vim.PerformanceManager'] CollectVmVdiskStats : Failed to get VFlash Cache stats for vscsi id scsi0:1 for vm 16

When I raised a support request on the issue, VMware Support advised they have seen this problem with a few other customers and there is a bug raised with VMware engineering. If you experience this problem contact support and provide them with logs to help track down the cause.

I'll post updates to my support request and hopefully the solution.

Re: vFlash performance metrics missing

PeterCr — Thu, 29 Jan 2015 23:23:43 GMT

VMware are expecting to patch this problem in the last week of April, the follow KB article will be accessible in the next week or so http://kb.vmware.com/kb/2106149

Re: vFlash performance metrics missing

PeterCr — Mon, 18 May 2015 22:24:59 GMT

VMware have released the patch which resolves this problem now.

VMware KB: VMware ESXi 5.5, Patch ESXi550-201505401-BG: Updates esx-base

The vFlash cache metric counters such as FlashCacheIOPs, FlashCacheLatency, and FlashCacheThroughput might not be available when CBT is enabled on a virtual disk. Error messages similar to the following are logged in the stats.log file:

nnnn-nn-nnT06:17:20.200Z [nnnnnnnn error 'Statssvc.vim.PerformanceManager'] CollectVmVdiskStats : Failed to get VFlash Cache stats for vscsi id scsi0:0 for vm 3
nnnn-nn-nnT06:17:40.189Z [nnnnnnnn error 'Statssvc.vim.PerformanceManager'] GetVirtualDiskVFCStats: Failed to get VFlash Cache stat values for vmdk scsi0:0. Exception VFlash Cache filename not found!
…
…
nnnn-nn-nnT06:18:20.181Z [nnnnnnnn error 'Statssvc.vim.PerformanceManager'] GetVirtualDiskVFCStats: Failed to get VFlash Cache stat values for vmdk scsi0:0. Exception VFlash Cache filename not found!

Re: vFlash performance metrics missing

PeterCr — Wed, 20 May 2015 02:22:58 GMT

Original KB is still inaccessible. Use this KB instead for more details.

VMware KB: vCenter Server performance metrics for Flash Read Cache do not display for virtual machines with CBT enab…