CIFS unresponsive under ESXi 5

[iks]

Hello,

I am running FreeNAS (FreeNAS-8.3.1-RELEASE-p2-x64) under ESXi 5.1.0. I am using VMXNET 2 (Enhanced) adapter for networking and this machine is used only as CIFS server, nothing else. There is no problem with network throughput as I am getting stable and constant 60-70MB/s on my home gigabit network. And my 2TB Raw LUN WD HDD is in ZFS pool. Everything is working great to this point and I am running this setup for some weeks.
But I am experiencing some kind of unresponsiveness of CIFS shares because:
- sometimes I just can't access some folders,
- windows explorer stops responding (because share is somehow dropped),
- sometimes explorer says that network share is no longer available (and after some reties it is working fine again)
and so on. And at those times even FreeNAS GUI is somehow lagged... Top command in SSH shows that machine is idling at 100% and all the processes are using 0% of CPU time.

I need to mention that before I went to FreeNAS I had the same HDD (Ext4) in Debian machine under ESXi using VMXNET 3 adapter and CIFS was working perfectly fine.

Does anyone know what is the problem here? Only thing that arises in my mind is that there's something with VMXNET 2, but I hardly believe that as transfer speeds are OK...
So any suggestions will be greatly appreciated...

My System Info:
System Information

Hostname ...
Build FreeNAS-8.3.1-RELEASE-x64 (r13452)
Platform Intel(R) Core(TM) i3 CPU 540 @ 3.07GHz
Memory 3056MB
System Time Tue Apr 23 18:06:17 CEST 2013
Uptime 6:06PM up 1 day, 23 mins, 0 users
Load Average 0.33, 0.12, 0.04
Connected through ...

Thanks,
-Andrej

 

[jgreco]

Only thing that arises in my mind is that there's something with VMXNET 2, but I hardly believe that as transfer speeds are OK...

If you had a car that could go freeway speeds but often stalls at a red light, would you say that you "hardly believe" it has a problem?

vmxnet2 is great except when it doesn't work, which is often enough. Use Intel E1000 emulation and move on with your life.

 

[iks]

If you had a car that could go freeway speeds but often stalls at a red light, would you say that you "hardly believe" it has a problem?

vmxnet2 is great except when it doesn't work, which is often enough. Use Intel E1000 emulation and move on with your life.

Hi, jgreco.

Thanks for your answer. So without all the hate that I have sensed in your post, you are merely trying to say that my suspicions are correct? I was just guessing that there's everything fine with VMXNET 2 adapter as it works good for 90% of the time and on top of that transfer speeds are good. So it looked good to me, but I was still suspicious. I don't need some car-related-comparison to enlighten my mind. I have done enough network stack related programming and I know how things are working... But I must say that I don't truly like any kind of emulation if there's paravirtualization available but if FreeBSD leaves me with no choices here, I will be more than glad to grab the one that works.

Thanks again, and chill out a little bit.
-Andrej

 

[iks]

Hey,

Well everything seems to be working perfectly fine with VMXNET 3 and even with jumbo frames enabled... I am happy now and am moving on with my life... :)

Regards,
-Andrej

 

[jgreco]

Great, good to know. There seem to be lots of little issues with vmxnet2, which we used (and came to regret using) heavily in our initial virtualization initiative, because stuff would randomly stop working or more esoteric issues would pop up, that would break things like CARP (we sat there looking at the known CARP on an ESXi ethernet trunk issue for quite some time but were running into something else). That, plus the device driver load ordering in bootup requiring a bunch of pain, well, anyways, all the problems vanished on new deployments without vmxnet2.

Sadly, vmxnet3 isn't available on vSphere 4. I should bug someone about vSphere 5... it'd be interesting to see if it works any better.

 

[pbucher]

I can also confirm also that vmxnet3 works great. Which is one of the reasons I do the virtual SAN thing, I can get 10Gb speed to my ESXi server without having a 10Gb network.

 

[iks]

Hello,

I know how it is when you are debugging something and running into something else... :)
Well VMXNET3 is definitely worth of further investigation as it is still working fine in my case, and I am not having any problems even with plugin jail on the same device...

Its too bad, that openvm tools do not include VMXNET3 modules, but the whole package seems to be pretty outdated...
But then again I don't know how it is with all the licensing for those modules...
And vSpehere 4 users are forced to use emulation anyway... :(

Regards,
-Andrej