Should Parallels really use so much memory?

B

Billymac231

Member
Hi.

I have Parallels for Desktop Mac version 9 running under Mac OS X 10.9 Mavericks on a late 2010 15" MacBook Pro connected to an Apple cinema display.

I just happened to notice this morning that there seemed to be a lot of memory being used on my Mac, even though I wasn't doing much with it, and so I launched Activity Monitor to see what it was that was using it.

There seemed to be two main 'culprits', a process called kernel_task which was using about 650MB, and a process called prl_vm_app which was using a staggering 1.4GB!

I don't know what kernel_task is, but prl_vm_app is definitely something to do with Parallels. (It isn't Parallels itself, because that shows separately in Activity Monitor as 'Parallels Desktop' and uses only around 15MB.)

So I shut down my Windows 7 virtual machine and then quit Parallels completely. I couldn't believe how much faster my Mac now worked. It was like a new Mac! Chalk & Cheese! (I remember feeling the same the day I got a new pair of glasses, not having realised how much my eyesight had deteriorated...)

When I re-launched Parallels, and my Win7 VM, I watched Activity Monitor, and although prl_vm_app wasn't too bad at first, it very gradually grew and grew in memory use, so that after about ten minutes of running the VM in Parallels it was using something around 955MB. And, of course, my Mac slowed down again...

Having said that, the memory pressure graph in Activity Monitor is still in the green.

Is this slowing down of the Mac side of things normal, or does it suggest that something isn't working right? Is there anything I can do to speed up my Mac when I have Parallels running on it, which is normally all the time in the background?

Thanks.
 
Kernel task is the core of OS X itself.
The RAM consumption of the Parallels process you mention is the memory being used by the virtual machine, if you assign 2 GB of RAM to it you see that process use up to 2 GB, depending on how the virtual machine uses RAM the value will vary, but the values of around 1GB for a Windows VM are totally normal.

Long story short, your Windows VM is using that RAM.

The slowing down might be related to RAM usage, yes, I don't know how much RAM you have but you might need to quit some apps to use Parallels at a faster speed, also, if the VM is running it will consume CPU also, this is to be expected, you are running 2 operating systems at the same time in the same computer.
 
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Oh, I see. That's fair enough then. Thanks.

Any tips on how to reduce how much RAM Windows 7 uses...? Or should I dig out that old Windows XP CD?
 
Right.

I've changed the VM memory usage from 1GB down to 512MB in the Virtual Machine > Configure... > General tab, and I've changed the performance in the Options > Optimization tab from 'Faster virtual machine' to 'Faster Mac'.

Anything else...?
 
512? What OS are you running on Parallels? Even XP only runs smoothly with at least 1 GB. If you are having memory issues you shouldn't be running Parallels at the same time you are doing something heavy on the Mac side, also, it would help to know how much RAM you have got.
 
I'm still running Windows 7 Home Premium as the VM on Parallels, but I don't do anything on it that is remotely memory-hungry. I only really run two apps on Windows: An old version of Outlook (for the Journal component in it that I use to keep a diary) and something called SBS-1 BaseStation, which is the software associated with my virtual radar receiver. I have now changed the Win7 theme to 'Classic', so as to get rid of the fancy aero-stuff in it.

I have 4GB of memory in my Mac, shown on 'about this Mac' as 1067 MHz DDR3.
 
512 is too little for Windows 7, specially if it's the 64 bit version, you should be running the 32 bit version. 4 GB is the minimum for running Parallels, slowness is expected in such configuration, but if the Windows side is working properly with this configuration then leave it at 512, but I expect you'll have some slowness problems with Windows.

Win 7 and OS X like to use RAM, and they both have to share 4 GB, so yeah, you can't run everything at the same time.
 
I upgraded my RAM a week ago from 4 GB to 8 GB. Unbelievable difference in performance speed after the upgrade. It's worth the hundred bucks or so for the additional RAM, if your Mac can handle it.
 
Docger said:
I upgraded my RAM a week ago from 4 GB to 8 GB. Unbelievable difference in performance speed after the upgrade. It's worth the hundred bucks or so for the additional RAM, if your Mac can handle it.
Click to expand...

Thanks Docger.

I looked on the Apple support site, and unfortunately, although my MBP is shown as having 'maximum' RAM of 8GB and it presently only has 4GB fitted, it says that there is 'no memory currently available' for my Mac... So it looks like I'm stuck with what I've got.
 
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