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Re: Terrible Performance with Windows 8.1 Guest
Posted: 19. Jan 2015, 19:25
by Perryg
http://ark.intel.com/products/76349/Int ... o-3_60-GHz
Code: Select all
00:00:04.051450 Logical host processors: 4 present, 4 max, 4 online, online mask: 000000000000000f
00:00:04.051607 Physical host cores: 2
Logical = thread. VBox deals with physical cores.
Re: Terrible Performance with Windows 8.1 Guest
Posted: 19. Jan 2015, 19:25
by loukingjr
Once in awhile the CPU is mismatched by VirtualBox in the logs…
0:00:03.320543 CPUM: Matched host CPU INTEL 0x6/0x3c/0x3 Intel_Core7_Haswell with CPU DB entry 'Intel Core i5-3570' (INTEL 0x6/0x3a/0x9 Intel_Core7_IvyBridge).
So as mpack said, you should only assign 1 core to the guest.
Edit: An Intel CPU cannot be both a Haswell and an IvyBridge for that matter.
Re: Terrible Performance with Windows 8.1 Guest
Posted: 19. Jan 2015, 19:40
by socratis
loukingjr wrote:Once in awhile the CPU is mismatched by VirtualBox in the logs…
VBox.log wrote:0:00:03.320543 CPUM: Matched host CPU INTEL 0x6/0x3c/0x3 Intel_Core7_Haswell with CPU DB entry 'Intel Core i5-3570' (INTEL 0x6/0x3a/0x9 Intel_Core7_IvyBridge).
Edit: An Intel CPU cannot be both a Haswell and an IvyBridge for that matter.
No, the log doesn't "lie" (unless it's a bug), VirtualBox simply picks up the closest match that they have in their CPU database. In this case, a
Haswell and an
IvyBridge are close enough for all technical purposes.
VBox.log wrote:00:00:04.051752 Full Name: Intel(R) Core(TM) i7-4600M CPU @ 2.90GHz
Re: Terrible Performance with Windows 8.1 Guest
Posted: 19. Jan 2015, 19:43
by loukingjr
It's still wrong.

Re: Terrible Performance with Windows 8.1 Guest
Posted: 19. Jan 2015, 20:57
by michaln
loukingjr wrote:no problem. still no guest additions or extension pack installed.
dozens if not hundreds of this:
00:01:18.980090 AsyncCompletion: Task 0x0000001abc8b80 completed after 11 seconds
00:01:18.980829 AsyncCompletion: Task 0x0000001abc8b40 completed after 11 seconds
00:01:18.981071 AsyncCompletion: Task 0x0000001abc8b00 completed after 11 seconds
00:01:18.981159 AsyncCompletion: Task 0x0000001abc8ac0 completed after 11 seconds
00:01:18.981396 AsyncCompletion: Task 0x0000001abc8a80 completed after 11 seconds
00:01:18.981578 AsyncCompletion: Task 0x0000001abc8a40 completed after 11 seconds
00:01:18.981704 AsyncCompletion: Task 0x0000001abc8a00 completed after 11 seconds
not sure if that is because of no GAs or extension pack or something else.
Neither. It means the host's I/O system is overwhelmed. As I said, (recent) Windows guests like to do that, especially in combination with something going on on the host.
Re: Terrible Performance with Windows 8.1 Guest
Posted: 19. Jan 2015, 21:52
by loukingjr
thank you michaln.
Re: Terrible Performance with Windows 8.1 Guest
Posted: 19. Jan 2015, 22:27
by klaus
Double checked with your log file... you're using the default SATA controller settings, i.e. disabled host I/O cache. It means that VirtualBox uses the async I/O code path, which has far higher throughput for random access patterns. This matches the other messages. It's definitely as others pointed out: the VM and all other applications on the host produce so much I/O load that your disk can't handle it in a reasonable amount of time.