VMWare 6.0 & Server 2012 R2 - 14.5GB Driver Locked RAM

[CHiLL]

We have our cashless catering and door access control system installed on a virtual server which has been allocated 24GB of RAM. Every few days, the server will slow down and the kitchen staff are unable to use the cashless catering system. A reboot of the virtual server will alleviate the issues, until a few days later and the same issue will happen again.

 

Now I've looked into it and found that Task Manager says that ~75% of the RAM is in use, despite it being 10am and in the middle of lessons, so the cashless system is not in use and the door access control system is not being used much. When I sort the RAM, the highest usage application is the cashless catering at a staggering 150MB, which does not account for the 75% usage.

 

When I open Resource Manager and use the Memory tab, 'In Use' memory is at 18.2GB, though none of the values within Resource Monitor add up to any where near this value.

 

I have used RAMMap from Microsoft's SysInternals and that shows more of the picture. It classifies 14.5GB of RAM as being 'Driver Locked'. I could do with it not being locked! So I did some research and came across many arcticles and threads suggesting that the RAM has been increased on the virtual server, but the limit has not, so VMWare will 'lock' the memory it is allocated but unable to use. I have checked our settings, and we do not have a limit, in fact it is set as 'Unlimited'.

 

Can anybody help shed some light on how I can free up this RAM?

 

Thanks!

[pantscat]

Is the memory on the host over-committed? i.e. more RAM allocated to VMs than you've actually got?

 

It sounds like it's the VMware balloon driver at work here.

[CHiLL]

Is the memory on the host over-committed? i.e. more RAM allocated to VMs than you've actually got?

 

It sounds like it's the VMware balloon driver at work here.

The VMWare Balloon driver is what I've found from the Googling. I've checked the host the server is on and it is not over-committed. 34GB free of 128GB. Our other host has 19GB of 128GB free.

[pantscat]

Ok - so you've got 128GB on that host available.

 

Is that 34GB free accounting for how much RAM is actually allocated to each VM? E.g. on each VM on that host, how much RAM have you allocated? Add all those figures up and see if it comes to more than 128GB.

[CHiLL]

Ok - so you've got 128GB on that host available.

 

Is that 34GB free accounting for how much RAM is actually allocated to each VM? E.g. on each VM on that host, how much RAM have you allocated? Add all those figures up and see if it comes to more than 128GB.

You may be onto something, it looks like we are massively over-committed on RAM. Host one has 144GB allocated and host two has 180GB allocated, despite both having 128GB each available. I am have devised changes to be made in reduction of RAM on servers that are currently over-powered and movement of servers from one host to another to balance up the usage. Some of the servers are too critical to take down at the moment, so I will perform those changes next week during half term.

[FN-GM]

Ok - so you've got 128GB on that host available.

 

Is that 34GB free accounting for how much RAM is actually allocated to each VM? E.g. on each VM on that host, how much RAM have you allocated? Add all those figures up and see if it comes to more than 128GB.

 

Don't forget some RAM is required to run the host OS.

[pantscat]

Glad that my many wasted evenings and weekends to become a VCP weren't wasted!

 

I take it you don't have VMotion then?

[pantscat]

Good point @FN-GM.

[CHiLL]

Glad that my many wasted evenings and weekends to become a VCP weren't wasted!

 

I take it you don't have VMotion then?

I am glad too! We do not have VMotion and I doubt we'd ever get it. For servers we want to edit or move storage, we can just arrange down-time for that.