virtualbox.org

You're welcome. I'm guessing that at some point you may have to re-run Onyx again. One thing you might check is whether "Use Host I/O Cache" is enabled for the SATA Controller. It might increase the cache over time. Although I have it enabled but I rarely ever use my Windows' guests.

More than likely. I've checked and the 'Use Host I/O Cache" isn't checked for the SATA VDI file, but it is enabled for the IDE DVD controller. Should it be enabled for both?

SpacemanSpiff wrote:More than likely. I've checked and the 'Use Host I/O Cache" isn't checked for the SATA VDI file, but it is enabled for the IDE DVD controller. Should it be enabled for both?

The IDE DVD controller default is enabled. The SATA IDE default is disabled but I usually enable it. It's been awhile but I think it makes guests read/write a bit faster. I've never done extensive tests however.

Thanks for the info!

Pleased that you are up and running.

I wonder if other "since Yosemite, slow" reports would benefit similarly.
And is easier than doing "clean installs" when performance is suffering

Well, after shutting down overnight and restarting in the morning, the VM was, once again, sluggish and stuttering.

I tried deleting the caches again but it's made no difference this morning.

This is getting so bizarre. Something is causing my VM to go screwy every morning, and I can't think for the life of me what it would be.

Several users with macs built before 2012 have reported success with the following: Prefix the boot-args value with debug=0x10.

In Terminal.app session, issue sudo nvram boot-args .
A response of nvram: Error getting variable - 'boot-args': (iokit/common) data was not found means the keyword has not been defined ===> value is Null

if the value is Null, Issue sudo nvram boot-args=debug=0x10
Else prefix the value as in sudo nvram boot-args="debug=0x10 -v"

Update: oh, yeah. Restart required

Source: https://communities.vmware.com/thread/493294

Thanks ChipMcK!

I've done this and it seems to have worked - the VM is smooth again - no stuttering in sight! I've also shut the iMac down, left it off for 5 minutes, then restarted, (hopefully) simulating a cold boot; it also worked after this cold boot.

I'll see how it goes today and tomorrow; assuming it's still working then I'll mark this thread as solved.

Thanks once again for all your help!

Just a messenger. DariusD deserves the credit/thanks

ChipMcK wrote:Just a messenger. DariusD deserves the credit/thanks

If DariusD is on this forum - thanks for helping me solve my issue!

@ ChipMck Good find. Just a clarification though. The problem according to the link you posted is limited to Mid-2011 iMacs. However seeing that SpacemanSpiff says he has a Late-2011 iMac that may not be entirely true.
I still have a 2011 iMac that has Yosemite on it and will test it later today.

@SpacemanSpiff DariusD is a VMware employee/developer.

loukingjr wrote:@ ChipMck Good find. Just a clarification though. The problem according to the link you posted is limited to Mid-2011 iMacs. However seeing that SpacemanSpiff says he has a Late-2011 iMac that may not be entirely true.
I still have a 2011 iMac that has Yosemite on it and will test it later today.

@SpacemanSpiff DariusD is a VMware employee/developer.

I've checked, and it was my mislabelling. I have a mid-2011 iMac. Thanks for the clarification on the DariusD issue (I thank them anyway, in case they happen upon this thread) …

other sources are
https://communities.vmware.com/thread/492900 and http://forum.parallels.com/threads/para ... te.326205/

I believe dariusd is a volunter

for certain macs a problem. Noted some laptop owners swearing on this.

Best to y'all! Merry Turkey Day to those observing.

ChipMcK wrote:
I believe dariusd is a volunter

Best to y'all! Merry Turkey Day to those observing.

dariusd

Happy TDay to you as well.

Well, after leaving it off all night, and coming back in this morning, I've turned the VM on again and … it's working. No sluggishness or weird behaviour! Therefore I'm pleased to be able to mark this issue as [Solved] …

I'm really very grateful to you all for helping me with this issue. Thanks very much

All the best to you and yours.