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I just purchased a new Macbook Pro to replace my aging 2006 model. I am running Lion with the latest updates, I have a 2ghz i7 processor with 4gigs of RAM.

I need this machine to do .Net development in Windows so I am running a Virtual Machine. I have tried both Parallels and VirtualBox (both the latest) to run Windows 7. On both of those machines I gave the VM 1GB RAM (and it runs fine-ish)

When I have the VM or any other program that uses a lot of RAM (like Steam, or Minecraft) the entire machine in OS X bogs down. When I say "bogs down" I mean launching new applications or opening new windows/tabs takes too long. After the new tab/window launches it runs fine.

An example would be that with Chrome open, if I open a new tab it may take up to 10 seconds for the tab to show up. Just opening the main menu to go to "About This Mac" took 3 seconds to open the menu and 2 seconds to open the window.

I would expect my VM to run slowly with only 1 gig of RAM, but I would not expect these issues to transfer over into my main OS.

Is Lion a known resource hog or does it sound like something may be wrong with my new machine?

For reference sake, the machine recognizes the full 4 gigs of RAM. Currently Activity Monitor says that my RAM stats are this:

  • 100mb Free
  • 2.3GB Wired
  • 1.12GB Active
  • 450mb Inactive

(those numbers are rounded)

I checked with a coworker running a Parallels VM of Windows 7 with 1GB RAM on his 2007 Macbook Pro and he has similar RAM numbers, but his machine is fast and responsive while mine is not. Even typing this message, there is a noticeable delay between me pressing a key and seeing it typed on the screen.

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Have you checked activity monitor for any other programs with high cpu usage and IO Disk activity? – Sandeep Bansal Oct 25 '11 at 16:27
I have watched Activity Monitor and the only high resource applications I have seen have been the programs I would expect (Parallels, Steam, etc.) – James P. Wright Oct 25 '11 at 16:32
up vote 1 down vote accepted

To answer your first question.

No, Lion uses far less resources then Snow Leopard.

With regards to your colleagues older machine performing better, make sure that he is running stock standard, and didn't upgrade specs to the max, or even just installed a better HDD. Also, make sure you work on it. I have often seen colleagues show me it works, and when actually using it on their machine, it gets as slow as mine did within an hour.

Having a similar spec to yours, the 2010 i7 15", I would highly suggest that if you planning to run VM the following is an investment worth making:

Replace the 5400RPM drive in it with a 7200RPM drive.

This is the first thing I did, and although it still wrote to disk a lot, it was at least less noticeable.

Upgrade to 8GB RAM

You can never have to much RAM, and seriously, I can run a 4GB VM with Windows 7 and still have 2GB free, no swap being used, and the drive is quiet and hardly noticeable.

Set you VM to give higher priority to OSX

In Parallels there is an option to optimize priority. Set it to OSX, and also make sure you switch off the Adaptive Hypervisor.

Last suggestion, make sure you have the latest Parallels. It is a huge performance improvement above any other VM solution, and previous Parallels solutions.

Lion has made changes, but I had the exact same problems on Snow Leopard. Just because the VM is given a small amount of RAM != better performance. The amount of swap file space needed to virtualize a machine can quickly kill performance. The key is to prevent swap file writes, and that can only achieved by most importantly pushing RAM to the max, and secondly by getting a faster drive.

I have heard horror stories about SDD's and VM's, so for safety sake am not going to suggest it, however it is worth considering.

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Excellent advice, and I have a feeling that the hard drive and ram may be my main issue. (also, the co-worker has an SSD) On that note, I bought 8 gigs of RAM for less than $50...can't see a reason not to make that change at all. Going to stick with the 5400rpm drive for now. Thanks for the advice on the Parallels settings too. – James P. Wright Oct 29 '11 at 17:07
@Pselus Fair enough. I know on my model, the 5400RPM stock drive only support a 1.5GB link speed while the card was capable of 3.0GB. The 7200 linked at 3.0GB and it made a huge performance difference. Also, if your coworker has an SSD, you cannot compare specifications. The SSD is a complete different ball game from a platter drive, and even with 2GB of RAM he will see a huge performance boost. – BinaryMisfit Oct 30 '11 at 11:02
@Pselus Lastly, although these tips will improve performance, don't expect it to be speeding bullet. There is times I have to kill my VM's to do something really heavy, and I never run my VM unless I really do need it. – BinaryMisfit Oct 30 '11 at 11:06
Got my new 8 gigs of RAM installed and it runs like a dream now. I'd say that either updating RAM or the HD would have really fixed the issue for me, but RAM was the cheapest at $50 for 8 gigs of G. Skill. – James P. Wright Nov 2 '11 at 21:36

You said:

if I open a new tab it may take up to 10 seconds for the tab to show up. Just opening the main menu to go to "About This Mac" took 3 seconds to open the menu and 2 seconds to open the window.

It most probably indicates that the machine is thrashing. Please run top in a terminal and check the number of pageouts and pageins. Lets assume that you see the following:

125745(0) pageins, 0(0) pageouts

The numbers before the parentheses, 125745 and 0 in this example, indicate the total pageins and pageouts, respectively, performed since this Mac was last restarted. Over time, both numbers will increase. If the total pageouts is low — ideally 0 — compared to the number of pageins after having used your Mac for hours of work, you may have sufficient RAM. Otherwise, you should install more RAM.

The numbers within the parentheses are the most important: these indicate the number of pageins or pageouts performed in the last one second. If these values — especially pageouts — are consistently in the range of 25 to 50 or more, then the system is thrashing: paging excessively as it is starved for RAM at its current workload. Overall performance will be slow as the CPU spends more time paging than on other work. If your Mac is thrashing, you need to install more RAM!

I recently faced a similar problem and checked this: Problems from insufficient RAM and free hard disk space and found that I had to increase my RAM. And the problem was resolved.

Lastly, it might also be the case that you are running very processor intensive tasks. If that is the case, then increasing the RAM might not help you.

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